The days to follow were ones of interest. The next day, Emerald went to Twilight's tower again as they continued with more experiments that the studious mare had set up for him. After each time they finished for the day, the mare would always kiss him as it divulged into a small session of passionate kissing. In the moment, both ponies gave in to their emotions as they acted like animals in heat, but once the moment died down, their brains switched back to normal as they just carried on like nothing happened. It did give Emerald some thought as to why it happened.

The stallion was currently in a tank of water as he was testing to see how long he could hold his breath. Twilight held a small stopwatch while timing all of Emerald's trials. The stallion was showing progress as he was now up to 10 minutes. Soon, the stallion emerged from the water tank as he took some mouthfuls of air.

"Not bad!" said Twilight as she stopped the stopwatch and wrote down Emerald's latest time.

The studious mare ignited her horn as she made the tank disappear and put Emerald back into his regular clothes. She floated over one of the energy tonics as he downed it and regained vitality.

"Well, you'll be pleased to know you've seen significant improvements since we started. Overall, your stamina, conditioning, and vitality, in general, have gone up by 12%. To put it into perspective, I've compared it to your test results during your physical exams for the Royal Guard."

"How did you manage to get my scores?" asked Emerald.

"I have my ways," said Twilight as she wrote down Emerald's final numbers.

"So, any other tests that you need me to do?" asked the unicorn.

"No. We're done for today. However, tomorrow, we'll be doing something different."

"Okay. What?"

"I got some errands to run."

"And what does that have to do with me?" asked Emerald.

"Whenever I go, you go. Remember," stated Twilight.

"So, you just need me to follow you. Like an actual babysitter?" said the stallion.

"Don't be late!" said Twilight.

"Well... at least I won't be stuck here," stated Emerald as he left the mare's lab.

Twilight watched until Emerald left. She then turned back to her journal as she made a book appear in a flash. The girl opened the book, and the cover was a statue of a mare and stallion, as both had no clothes. The lavender unicorn turned to a specific section of the book as she began to take notes.

"Everything is going according to plan," said the mare as she devised and worked out the final details of her experiments for the next part of her independent study.

---

The next day, Emerald arrived at Twilight's tower at the designated time the mare asked him to come. The stallion saw the mare putting several books in her satchel as she had to stop by the Canterlot Library to return some things. The pair went to the library as Twilight returned the books she rented. Once that was taken care of, the pair began to get on with Twilight's chores, or rather, the mare did as Emerald just stood by and watched while keeping an eye on her.

"So... Ms. Sparkle..."

"You can call me Twilight," stated the mare as she looked over some garments. "As far as I know, nobody knows you're a Royal Guard without identifying your uniform. So unless you want to draw attention by always referring to me as Miss, call me by my name. Besides, you're my assistant, so... act like it."

"What do you mean?"

Emerald soon got his answer as he was starting to be handed things. The stallion was seeing what the studious mare meant as he was starting to become her personal pack mule. Twilight began to throw clothes upon clothes one by one as they soon buried the stallion under it.

"Come on. Keep up!" said Twilight as she walked away with Emerald sighed before using his magic to make the giant pile on top of him float and land in his arms as he carried them.

"So... Ms, I mean, Twilight. Care to tell me a bit about yourself?"

"And why would I do that?" asked the mare as she eyed the stallion.

"Cut me a break, please. I already agreed to be your lab rat. The least you can do is answer some questions I have about you." stated Emerald.

Twilight sighed as she looked at her guard.

"Very well. If you must know, I'm a child of two. I have an older brother. You should know who he is: the Captain of the Royal Guard."

"C-C-Captain of the Royal Guard?" said Emerald as he got a bit scared after hearing that. "You mean to tell me that... your brother is..."

"Yup," smiled Twilight as she got in the face of her guard. "So... if you do anything that I disapprove of. Well... you better start running."

Emerald gulped as he felt a slight terror after hearing Twilight mention who her big brother was. The mare seemed to notice that the stallion before was affected by her statement as she smiled. She then turned back around to a rack of clothes as she noticed something.

"Oh wow, this is simply amazing," Her fingers slowly move across, feeling the fabric of a t-shirt with the picture of a kitten. Twilight just brushed over it as she just looked over. It looked to be around her size as she gave a smile.

Soon, almost as if on cue, a mare wearing a black polo shirt and black jeans moved. She was a slightly tanned mare, blond-haired mane and tail, clearly wearing too much makeup, with her tits out in the air. She smiled, looking over towards Twilight first, giving a smile.

"Hello, miss. Is there anything I can help you with?" asked the salespony.

"No, thank you. Just looking to buy some stuff. But I do ask, do you have a changing room nearby?" asked Twilight.

"Right over here," said the mare as she led Twilight, who gestured for Emerald to follow as he had no choice.

"Here you go. If you need anything, feel free to ask," said the mare.

"Much appreciated," said Twilight as she used her magic to place the giant pile Emerald was forced to carry and set it on one of the chairs behind him.

The studious mare told the stallion to take a seat as she used her magic to pull some of the clothes with her as the door shut with a thud. The stallion sighed as he slumped in the chair, glad to finally get a rest from all the carrying he had to do.

"And is there anything I can help you with, sir?" asked the mare to the guard.

"Oh, no. I'm not shopping for anything."

"Are you sure? 'Cause we happen to have a sale on suits. 50%." asked the mare as she tried to use her skills to convince Emerald to buy.

"Again. I appreciate the offer, but I'm good."

"Very well. If your girlfriend needs anything, don't hesitate to ask," said the mare as she left.

"Girlfriend? Um, she's not my..."

Emerald tried to tell the mare that Twilight was more of an acquaintance, but she was long gone.

"Hey, Emerald. Can you help me? I need your advice on this." said the mare.

The door was pulled open as Twilight stood with a too-big shirt and baggy jeans.

"Am I really that small?" asked the mare.

"Well, I'm probably not the most keen expert on fashion, but they seem to be a tad bit big," said Emerald.

"I knew it. Thanks. Oh, and I need you to do something." The mare made a clipboard appear in the stallion's hand as a quill also appeared. "I need to hear your thoughts and scores for every outfit I try on."

"Why?" asked the stallion.

"Remember. Clause #1. You do whatever I say with little to no rebuttal. It's for the independent study." stated the lavender mare.

"Fine," sighed Emerald.

The mare smiled as she closed the door and changed into another set of clothes. Emerald began to scribble on the clipboard as he wrote down Twilight's first outfit, made notes about it, and scored it using the princess' rubric. The second outfit Twilight emerged with was a simple one. A yellow T-shirt that fit her more comfortably and shorts that stopped above her kneecaps. Emerald had a blank look as he just wrote down the mare's attire and gave it the appropriate score using her rubric. One by one, Twilight was trying on different outfits and getting some feedback from Emerald on his opinion. In the end, the studious mare ran through 20 different clothing combinations.

"Alright, how about this one?" asked Twilight as she opened the door and presented herself.

The mare wore a pink sweater jacket with a hoodie; she tied her mane into a bun and put on a pair of cosmetic brown oval-shaped glasses.

"Heh. Cute," admitted Emerald as he wrote that down.

"Is this too casual or not enough?" asked Twilight.

"It works. If anything, this is probably the best outfit I like," Emerald said.

"I see. In that case, I'll also take this one.

"Great. So we're done?" asked the stallion.

"Just... one thing," said Twilight as she snapped her finger.

Another pile of clothes appeared next to Emerald as the stallion knew what that meant. He leaned back and groaned, only for the clipboard he was holding to vanish. Soon, the clothes next to him also floated into the room.

"Don't worry about taking notes for these," smiled the mare as she closed the door. "Okay. Now, onto... the next part of the experiment. I'm... nervous."

"Well, at least that's less work on my part," said Emerald.

"Alright," said Twilight as the door opened.

Emerald reeled his head back down and froze upon seeing the mare. Twilight stood in a bathing suit; however, the stallion was at a loss as the sight before him left him speechless. That bathing suit, already a tight little number that barely matched the width of her arm when it was on a rack, was being stretched to the limit over Twilight's divine curves. Her ass struggled to keep its heart shape over the dip of black leather biting into her cutie marks. And the funbags up front? Being squished into those straps made her cleavage look like a canyon!

Emerald felt a sudden feeling inside, and all the blood in his body seemed to stop rushing to his head as he looked at this... this... angel before him. Twilight was shown to be a bit nervous as she stood there with her arms behind her back and was nervous about revealing this much to someone she barely knew.

"So... um, do you... like this one?" asked the nervous mare.

"Um... um, well, I... I..."

The guard was fumbling and stammering up a storm as he couldn't give the mare a clear answer. Mainly due to the fact of the view he saw before him. Twilight could see that despite her nervousness, the next part of the book she rented out of showing herself in these outfits worked as Emerald couldn't speak straight. She immediately closed the door and was shown leaning against it as she slid down. The mare put a hand to her chest as she could feel her heartbeat kicking up.

"That was... scary. But... also thrilling," stated the mare as she remembered these feelings for accurate data points. "Okay, breathe, Twilight. You still have more trials to do. Breathe." The unicorn took a minute to compose herself as she willed herself to overcome her nervousness to continue this part of her independent study.

When Twilight closed the door, Emerald immediately regained the working function of his brain. The stallion put a hand to his head as he was processing what had happened. Twilight had come out in a bathing suit that really showed her off, and upon seeing it, he felt like he couldn't give her a straight response. With her gone from his field of vision, he regained the oxygen needed to speak.

"What... was that?" said the stallion to himself.

"Emerald. Are you okay?" called out Twilight from behind the door.

"Y-Yeah. Just... needed a moment," said the stallion to the studious unicorn.

"Okay. So, how do you feel about this?"

The door opened as Twilight showed off her next set. Twilight kept the top of the bathing suit as she added some jean shorts. Safe to say, if Emerald thought Twilight was sexy before, the new piece of garment elevated that. The guard had a perfect view of that bobbing rack of chest meat once restrained by the outfit. Those tits of the lavender mare had the perfect bit of bob, sag, and heft—enough for him to be certain they were real and spectacular. Her ass, while safely encased in that pair of jean-shorts she'd had, still peeked out from that tight 'V' of denim and the pink lace of a very elegant pair of low-cut panties.

"Well?" asked the mare.

Once again, Emerald was at a loss for words. Twilight, now a bit more confident, showed herself off at her guard. While still trying to come up with words, Emerald gave the mare a nod as that was enough for the lavender unicorn. She closed the door and began to change once again. This time, Twilight came out in a bit more revealing and even more sexy clothing. Twilight was standing there, wearing a very revealing teddy. The fabric was still slightly showing off her nipples while they stuck out; it was a crimson red that managed to show off her body. At the same time, she swayed back and forth. The guard's response this time had him dropping his jaw; Twilight did another brave act on her part as she slid her hand over her body, caressing her fingers as she kept her eyes on him like he was the only pony in the entire world.

"Do you like what you see?" asked the mare.

Emerald's brain was too far gone as he nodded at this point. The stallion admired the voluptuous mare standing before her as she showed herself off to him. Twilight closed the door again and began to change. This went on for about a while as Twilight tried different clothing combinations. Among the different assortments, one of Emerald's favorites was a corset with a white g-string since it showed off her frame even more delightfully while she was modeling for him, as she gave a wink. Emerald groaned as underneath his pants, he had a somewhat bulge that had been slowly growing with each of Twilight's outfits, and right now, it was pretty noticeable if one looked down.

As for Twilight, she merely caught a second glimpse of it, and she could see that her book was right, which meant that when they got back to her lab, she could proceed with the next phase. As for right now, the mare used her magic to make Emerald move from the chair into the changing room with her as the stallion was against the door, with the mare having her arms around his neck. Right now, the pair acted like they were the only ones in the world as Twilight's knee instinctively rubbed against Emerald's groin. The stallion felt it as he tried hard not to make any sounds to avoid them being discovered.

Thought with how they were positioned and the fact that he could feel Twilight's breast pressing into him, he could feel his brain slowly slipping. Feeling them against him, he could tell they were soft and full; it took whatever willpower he had control over not to reach a hand up to touch them as he feared even more trouble.

"Do you like what you see? Is it sexy for you?" She leaned in closer, her lips close to touching his.

"Yes, it's perfect for you." Emerald would whisper back slowly, getting more into it as he was inches away from her lips.

The two kept their gazes on each other as they soon met. Their lips touched. It was a simple peck that lasted a good five seconds. Upon releasing, Emerald brought a hand up as he gently gazed at Twilight's cheek, to which she leaned into it with her eyes closed and let out a soft moan. Before anything else could happen, Emerald's other hand fell on the doorknob as he grabbed it and quickly allowed himself out. Twilight looked at the door and felt a tinge of sadness but soon smiled as her book turned out to be correct. Following all the steps and procedures that her book told her, she was, for sure, ready to start the next stages of her independent study when they got back to the tower.

Outside, Emerald was bent over with his hands on his knees. The stallion was breathing profoundly heavily, almost like he had a heart attack. And it was given how close he was to Twilight in that outfit and how he felt her kneecap rubbing against his phallus.

"Is there anything I can assist you with?"

"Ah!" yelped Emerald as the salesmare from before spoke and spooked him as he fell over.

"Oh, dear. My bad. I didn't mean to startle you." said the mare as she approached him.

"It's okay," said Emerald as he sat up. His little buddy had now softened as it seemed his fear made it go down, to which he was thankful.

At that moment, Twilight exited the changing room back in her original attire as she had neatly folded all the clothes she tried on.

"And you, miss. I take it you found what you liked?"

"Indeed. I'll also be taking these," said Twilight as she presented the folded pile of clothes that she noted Emerald liked from his expression and gave them to the salesmare. During the rest, she snapped away back to their original spot.

"Excellent," said the mare as she began to take the pile to the counter.

Twilight looked down at Emerald, who sat beside her on the floor as she smiled. The mare began to walk in front of the stallion as she headed to the counter. The guard sighed as he got up and dusted himself off as he began to head over to where the studious mare was as it was time for him to be pack mule again.

---

Once Twilight paid for her clothes, she carried one bag along with her satchel across her body. As for the remaining bags, Emerald was stuck carrying them. It wasn't long before they arrived back at the mare's tower as Emerald struggled to climb, given he couldn't see over the bags. Twilight's voice was the only guidance as the mare did her best to instruct the stallion where to place his foot.

"And now turn left," said Twilight.

Emerald did that; he bumped into the edge of the mare's bed and fell over. The bags tumbled as they all landed on the mattress. He turned around and looked at Twilight as the mare sighed. She shook her head before her horn lit up and collected all the bags and clothes that fell as she neatly put them in her closet.

"Sorry about that," said Emerald with a sheepish smile.

"Just follow me," said Twilight as she set the bag she was holding and approached her bookcase.

The mare reached up to unlock her hidden door as she pulled the specific book back. It triggered the mechanism as it slid to the side and revealed the wooden door. The mare began to walk down the steps as Emerald took a moment to collect his breath from all his carrying before venturing into the lab. He noticed the mare had slipped on her lab coat and put on those useless glasses as she wrote down her observations that she noticed during her little modeling for the guard. Twilight mumbled to herself as she looked at the book she had checked out earlier for reference and looked up something as it would be crucial for the next step of her independent study.

"So, anything..."

"Do you find me attractive?"

Emerald was totally caught off guard by what he had heard. The stallion was left in a state of confusion as Twilight turned to face the guard.

"Do you find me... attractive?" repeated Twilight, though she spoke slightly softer.

"Um, well... I..." Emerald was rubbing his neck as he struggled to find the words. But who could blame him? Twilight just pulled that question out of her flank and point-blank asked him without any hint or buildup. In the end, the unicorn nodded.

"A nod won't suffice," stated Twilight. "I want a direct answer." The studious unicorn approached the guard; she got close to him and wrapped her arms around his neck to ensure he didn't try to escape and forced him to look her in the eyes to avoid any attempt of bluffing. "Do you find me attractive?"

"I-- I. I think... you're a very pretty young mare in your own right," said Emerald.

"Just pretty?" said Twilight.

"No... I mean, you're talented. Smart, very smart. And... um, well-"

Twilight sighed as she knew what Emerald was doing. She let go of him and turned around. She didn't show it, but her fingers were dwindling as she prepared to ask her subject the next question.

"How did it feel?"

"Excuse me?"

"My chest. When I pressed it against you in the changing room, how did it make you feel?" asked Twilight.

"I... I don't think..."

"I want an answer! Need I remind you of the contract you signed!" said Twilight, as she needed Emerald to answer her question as part of her independent study. "Be honest."

The guard ran a hand through his mane and rubbed his neck as he recalled when Twilight pulled him into the room, and he felt her breasts pressing up against him.

"It felt... nice. Everything about it. How it felt, how they looked."

"Did you imagine... touching them?" asked Twilight as she got even more personal.

"Yes. I... imagine what they would feel like," admitted Emerald as he rubbed his neck.

Twilight didn't say anything as she stood there with her back turned. A long period passed as it was nothing but silence. Emerald began to sweat a bit as this was the longest silence between the two ponies. Soon, she turned and approached the stallion.

"Close your eyes," said the mare as Emerald raised an eyebrow. "Close your eyes."

Emerald complied as he did what the lavender unicorn asked of him. Twilight was now taking some deep breaths as she prepared herself for the next step she was about to take. Soon, the sound of clothing was heard.

"Okay. Open your eyes."

Emerald did that as he was taken aback by what he saw. Standing before him was the studious mare as she was on her knees. And in front of her was his phallus as it was semi-hard; the unicorn had unzipped his chaps and slid down his garments just under his cock as it was directly into her face.

"Twilight... what..."

"The next procedure of the study. We've already done simple gestures, feelings, and, as of today, feeling one's posture above the waist in the changing room. Now is the next part, sexual stimulation." said Twilight.

"Um, sexual stimulation?" said Emerald.

"I'm sure you recall when I rubbed my knee against your phallus and testicles," stated the mare as she stood up and used her scientific term to address the guard's genitals. "Well, I need a sample of your seminal fluid."

"Seminal fluid? Why don't you just call them..."

"Because I have to use the correct terminology. I can't just go around calling it a... a c-cock and... calling them balls. That wouldn't be scientific." stated the mare.

"It'd be easier," said Emerald.

"Enough with this discussion. Now then... have you ever masturbated?" asked Twilight as she picked up a clipboard.

"What kind of question is that?" said Emerald.

"A perfectly normal one. So, have you ever masturbated?" repeated Twilight as she pushed up her glasses.

"I... I mean, yeah, who hasn't? But I do it in moderation." admitted the guard.

Twilight wrote down his answer as Emerald felt a tad bit weird. And not just because he had his pants down, showing his package in front of the mare, but also because she asked that question.

"Show me."

"WHAT?!!!" said Emerald as he almost yelled.

"Demonstrate to me," said Twilight as she repeated her statement calmly like it was almost normal.

"You're asking me to... crank one out?!" the guard stated.

"If it's not too much trouble," said Twilight as she responded in that same tone.

"You don't just... ask someone to let one out? That's... that's..."

"We're both young adults, and we're mature enough. As far as I'm concerned, we're the only ones here."

"Y-Yeah, but... I... you..."

Emerald was at a loss for words as he couldn't figure out how to put this situation into logical reasoning for Twilight. Ultimately, the stallion couldn't find the explanation, so he gave up and sighed. The guard looked at his little buddy and put his hand on it. With a deep breath, he began to stroke it. Despite not looking at her, the guard felt Twilight's gaze. Yet, as he continued to stroke, he found it to be a bit difficult. Twilight kept a keen eye on her subject. Observing his technique and seeing his face, trying to see what was occurring in his mind. The studious mare could tell the stallion was having difficulty doing the task she requested.

"Is there an issue?" asked Twilight.

"No shit!" said Emerald as he stopped stroking and looked at the mare. "You asked me to... jerk one off out of nowhere? What do you think? We guys can just let it rip whenever we want?" shouted the guard.

"Well, according to data. Across age groups, more males are reported to masturbate than females. About 73.8% to 48.1%." said Twilight as she tilted her glasses.

"Man, we give ourselves a bad rep," muttered Emerald after hearing the numbers regarding male masturbation.

"Okay, how about this? What if I help you by enticing a reward of sorts?" stated Twilight.

"A reward?" said Emerald.

"A positive reinforcement proves to be an effective way of motivating someone," explained Twilight.

The mare then began to take off her lab coat as it dropped to the floor. Emerald was confused until he saw Twilight remove her shirt, leaving her in her bra. The guard gulped as he saw her purple-colored bra that matched her skin as she undid her hair bun but kept her fake glasses on.

"Perhaps this will help. I want you to envision my breasts. You can look at them if it helps you to achieve ultimate pleasure." said Twilight.

"I'll... try," said Emerald, already staring at the mare's breasts through the fabric. And how they were pushing against it, almost begging to be freed.

The stallion put his hand back on his package as he lifted his gaze to be fixed on the mare's breasts. Immediately, he felt a difference, as he felt his cock starting to grow a bit just by looking at the purple mounds on the unicorn's chest. Emerald began to stroke as he kept his gaze on Twilight's chest and envisioned those purple wonders. Twilight also noticed the change in Emerald compared to his first attempt as she wrote it down on her clipboard.

In the guard's mind, Twilight's breasts were just the perfect size. The stallion had seen the images of all the porn magazines his comrades had as they often asked him for his opinion on the featured mares. To Emerald, he felt like the sizes shown were nothing but imaginary as they didn't seem real. But Twilight's... they were anything but fake. The pale, curved flesh bulged from the back lace of her bra; they almost seemed to glow against the dark fabric. They were large enough to fill his hands comfortably and balloon against his fingers as he squeezed. Emerald found his hand moving faster, his hesitation vanishing.

"Interesting," muttered Twilight as she wrote down an observation. "What are you thinking?"

"Your... breasts," said Emerald as he vigorously pumped himself.

"Any specifics?" asked the mare.

"Really?" said Emerald as he grunted.

"Remember," stated the mare.

"Fine. I envision... touching them. I picture myself squeezing them, touching them to feel their fullness. I imagine putting my cock between those lush mounds and even sucking them off."

"Suck them?" said Twilight as she wrote that comment down. "Anything else?"

"I imagine having my way with you," said Emerald as he could feel himself reaching his limit.

In the stallion's mind, he saw Twilight sitting on her bed as she was naked. The mare then spread her legs out to reveal her hidden treasure, enticing the guard. In reality, Emerald had backed up to a desk as he gripped it with his free hand to steady himself upon reaching his ultimate climax. His hand moved the fastest since he started as Twilight noticed the guard was about to finish. Within seconds, Emerald grunted as jets of white semen flew from the head of his cock and onto the floor. He kept jerking as a few more powerful spurts occurred before finishing.

The stallion was leaning against the edge of the desk as he breathed heavily. Twilight, who had been watching this experiment, was shown writing some things down as she took some notes. She flashed her horn; next to Emerald was a vial of the energy elixir as the stallion looked at the mare. She gestured her head for him to drink it as Emerald grabbed it and brought it to his lips.

"How do you feel?" asked Twilight as Emerald gulped the last of the tonic.

"I'm good," said the stallion as his vitality returned after jerking off as the mare asked. "So, can I finally pull up my pants?"

"Not yet," said Twilight as she wrote some things down.

"Come on! I just jerked himself off in front of you! What else do you need?!" shouted Emerald, as he felt he had made enough weird requests for the mare.

Twilight took off her fake glasses and set them down. Her back was turned to Emerald as she was shown reaching behind and unclipping her bra. The guard was stunned seeing her do that, and he didn't notice Twilight was on her knees and in front of his cock until he felt his tip bump gently against her nose. The stallion was stuttering as he didn't know what was happening.

"What are you doing?" said the guard.

"A good experiment doesn't just use one piece of data. For consistent results, you must conduct multiple trials. And this one requires a hands-on approach." said Twilight as she observed Emerald's phallus. "Plus, I'm a mare of my word. Since you did what I asked, I will reward you."

"Reward?" said Emerald.

"You mentioned about feeling my breasts. And how you want to... stick your... your... c-c-c-cock in between them," said Twilight; she almost didn't want to call Emerald's package by that word as it felt dirty. No pun intended.

Emerald didn't know what to make heads or tails about this situation. Per her request, having to jerk himself off in front of the mare was weird enough. Now... having the mare before him and about to let him bury his cock between her beautiful breasts. This had to be a prank. Some form of blackmail that she was recording to present to her mentor. It had to be. There was no way a mare this intelligent, innocent, beautiful would let this happen. Right?

But according to Twilight's expression, it didn't seem to be. He looked into her eyes as it seemed the unicorn was dead on doing what she wanted.

"Time to acquire a sample for my research," said Twilight. "Before I begin... can I ask? Do you like them? Are they... too big for your liking?"

Emerald couldn't believe it. This mare kept catching him off guard. Whether by her actions, the questions she asked, or whatever she requested of him. Just... how did she constantly do it?

"Well..." asked Twilight as she awaited an answer.

"Yes."

"R-Really? You... like them? I mean, even if they're a bit big."

"I don't mind. It just means... that there's more to love. Besides, to me... they're perfect."

"You... heh. You're a smooth one, you know. Hearing you say that... it... make me feel... well, I don't know," said Twilight as she looked up at Emerald. "Well... go on. Go ahead and touch them. I don't mind if... It's you. Just be gentle. Please. They're... sensitive."

Emerald looked at the mare as he raised his hand slightly to touch them. Upon contact, Twilight winced as she felt Emerald's hands, the muscles in them as they began to get to work. The fingers felt her breasts as they dug into her fur and how they rotated them. Soon, the stallion made the unicorn stand up as he leaned in for a kiss. The mare wrapped her arms around his neck as Emerald kept fondling her breasts.

"Oh...oh. Mmmm...oh. Oh, that feels so good. That feels so good! I...I never thought it would feel this good." said Twilight as she broke from their kiss and looked down to see Emerald's hands making her feel such wonderful pleasure.

Emerald brought her in for another kiss as his hands continued their assault. The stallion's hand made Twilight's nipples hard as the mare felt her body react to the sudden jolt as she gasped.

"Stimulant... pleasure..." said Twilight as she repeated her thoughts to write down for later. "You... can suck on them, now."

Emerald gasped after hearing that as he looked at the mare in the eyes. A nod and seeing her consent, he dove his mouth onto one of her breasts as Twilight lost it and moaned.

"Mmmpf! S-Suck on them! Oh, yes, yes, yes!" said Twilight as this pleasure was indescribable. There was nothing in any of the textbooks that she read that mentioned how good it would feel. "Don't stop! Keep going...please. Your tongue feels so good! Your hands feel so good! Mmmpf!"

The stallion soon put his hands on Twilight's waist as he lifted the mare. She wrapped her arms and legs around him as he turned around and set the mare on the desk. Twilight removed her arms and leaned back to pump her chest out as Emerald continued to devour one of her breasts while rotating and caressing the other, all while Twilight reeled her head back and let out moans of intense pleasure.

"Oh, yes! Oh, yes, yes, yes! Oh, keep doing that! That feels incredible!" said Twilight as she felt in heaven.

Soon, Emerald ceased his assault on the studious mare as she lifted her head to look at the stallion. The lavender mare looked at her guard as he grazed her cheek. Twilight unhooked her legs from around Emerald's waist as he stepped back; the mare then got off the desk as she bent down in front of the stallion, and was eye to eye with his now rock-hard cock. She touched it with a finger, and it twitched in response; Twilight was observing Emerald's cock.

"It's so big and...wow. Sorry, I...I'm not used to this. Seeing a real one and having a real live one right in front of me is much better than in my research. Just seeing these big testicles...and this penis...oh, and that smell! Oh...I never imagined how strong it would smell. It's so masculine. Oh...this might require additional investigation in the future...if you'd be up for it."

"Sure," smiled Emerald.

"Okay... ready," said Twilight as she was prepared to execute the next part.

The mare grabbed her boobs and used her magic to guide Emerald's cock as it was wedged perfectly in between them. Upon contact, both felt good, and it only got better as Twilight began to move her breasts as they rubbed along the stallion's penis.

"Does it feel good?" asked Twilight as she kept moving her breasts.

"Y-Yeah," said Emerald as he found it hard to respond, given how good of a job Twilight was doing. Safe to say, the imagination that he had earlier about feeling his cock in between her breasts was even better in reality.

"Oh, good. This is so exhilarating! Having your big, manly...cock snuggled between them...it feels so intimate. I...I can feel you. I can feel how hot you are. I can feel how hard you are. I can feel you throbbing. Can you feel me?" asked the mare.

"Yes, Twilight. They're so soft. And warm." confessed Emerald as he patted her head to signal he was enjoying Twilight pleasuring him.

"Glad you like it? Is there... anything I can do to make you feel even better?" asked Twilight.

"C-Can you... talk erotic?" asked Emerald.

"You mean... like what my books say as 'talk dirty'?" asked Twilight.

The stallion merely nodded as Twilight recalled that section of the book. It was a form of foreplay conducted between a male and female to help increase arousal and mutual sexual pleasure. The studious mare thought about it as she looked at Emerald and began to do as he requested.

"How does that feel, huh? Can you feel my breasts stroking your big, hard, meaty cock?" said Twilight as she began to talk dirty.

"Y-Yes," said Emerald.

"I'm gonna move faster. You want me to?" asked the mare, keeping up the act.

"Yes!"

Twilight smiled as she picked up the speed of her breasts. With Twilight upping her speed, Emerald nearly lost it at how much more it felt.

"It feels so good having your big, hard cock fucking them! You're making me feel...so hot. Go on! Fuck my tits. Thrust as hard as you want." said Twilight as she egged Emerald on.

"Be careful what you wish for," stated Emerald as he managed to speak and put his hands on Twilight's shoulders. The stallion then began to thrust as hard as he could.

"Oh, fuck! That feels so good!" said Twilight as Emerald made her feel good. "Give it to me! Give me your cum! Give me everything you've got! Give it to me! Give it to me!"

Twilight yelled for Emerald to release, and a few thrusts later, it happened. The stallion groaned and grunted as, from his penis, he fired several shots. Some of them hit Twilight's face and dripped onto her breasts as the stallion let loose all he held back from the insane and intense sexual pleasure. The guard kept his cock, now slowly softening, in between Twilight's breasts as it rested there. Twilight felt the semen of the guard on her face as she wiped some on her finger and looked at it.

"Consistency. Sticky. Thick." said the mare as she brought her fingers to her mouth and licked the liquid off her fingers. "Tasty. Sweet, yet salty."

The studious mare then began to lick the semen on her breasts slowly; she used magic to make the liquid on her face dribble down toward her mouth as she licked it off. The mare swallowed the stallion's cum with one gulp as she opened her mouth to show she had downed it completely. Emerald looked at the mare licking his cum as it made Twilight look hot; the sight of this academic and intellectual mare and how she was slurping up his semen like a common whore was almost enough to make his cock regain its hardness.

"I'm sorry."

"What for?" asked Twilight.

"I... I kind of lost control there. It's just... You felt so good that I-"

"It's okay. I'm glad that I could make you feel good," said Twilight, as she wiped the last bit of Emerald's cum and looked at her fingers. "It smells so good. And it tastes even better." The mare sucked on her digits as Emerald found it hot, seeing Twilight work her tongue. "Mmmm...oh! Oh, that's good! That tastes so good! Where...Where's my notebook? I have to write down these observations! This is valuable data!"

Twilight got up and removed Emerald's cock from her breasts as she headed to where her clipboard was. She didn't wear her bra or upper clothing as she was too focused on writing down her observations as if she would forget them.

"We are definitely doing this again! After this...I'm motivated to continue this independent study of male-female relations even more," said the lavender mare as she furiously wrote her notes.

Emerald began to pick up his pants and undergarments as he eyed the mare. She was too focused on cross-referencing her notes and checking her book as she made some edits. The stallion could see that she was so busy engrained in her books that he knew it would be pointless to get her attention.

"So..."

"That's all for today!" said Twilight, scribbling something.

"Right," said Emerald as he used his magic, and in a flash, he was fully dressed.

The stallion took one last sip of the tonic as he regained vitality. He looked at the mare, who was still topless and writing down. Emerald put his hands into his pockets and slowly walked up the stairs. He looked back at the mare before heading out as their little session was complete, and the pair were now acting as if nothing had happened. Ultimately, the guard began to leave the tower as he returned to his quarters, leaving the studious mare to her studies.

Next Chapter: Chapter 4: Orgasms and Showers Estimated time remaining: 2 Hours, 4 Minutes