With the final bell of the school day having long-sing rung, the halls of Canterlot High were largely empty, save for one or two students that had decided to linger about and catch up with a few friends. Among those who remained at this time were none other than Adagio and her sisters, who walked together with purpose towards a somewhat familiar locale.

"Okay, what do they want this time?" Aria asked with a grumble.

Adagio shrugged her shoulders.

"I haven't the faintest. But, the message said it was important, so we might as well go and see."

Sonata then looked to her two older siblings with a wide smile.

"Oooh! Maybe it's another present! Like when they gave us our pendants back?"

Adagio smiled to that memory, placing her hand carefully upon her recently-reconstructed necklace, before turning to her younger sister and shaking her head.

"I doubt it, Nata. But, I suppose it'll still be an interesting visit."

Sonata seemed a little down at that, but perked up soon after, for it was not long before the three of them caught sight of their destination. As per usual, it was the door leading to the music room, which had undoubtedly become the favourite hang-out spot of them and their friends. However, today, they were caught by surprise to find that Sunset Shimmer was here, leaning against the door herself. When she caught sight of Adagio and her sisters, however, she stood upright, took a few steps towards them, and bore a look that was, for lack of a better word, embarrassed.

"Girls, just for the record...I did everything in my power to try and stop her."

Naturally, a remark like that caused just a slight degree of concern for the three Sirens, who glanced warily at one another. As for Sunset, she simply let out a sigh, turning to the door behind her and opening it, stepping aside for her former enemies.

"Well...she's waiting."

For a brief moment, the three Sirens displayed a flicker of hesitancy, but, never wanting to be one to back down, Adagio took on a more determined look, marching forward, with her sisters close behind. It was not long before they were within the music room, and here, they took on looks of surprise. Twilight was here, looking about as eager and excited as they'd seen her, but what caught their interest most was that she'd clearly done some redecorating in here. Instead of looking like a typical music room, the place now seemed to be more akin to a traditional classroom, though there were only a handful of chairs. At the end of the room was a board with many notes and pictures pinned up, with Twilight herself still making a few adjustments to them. Entering in earnest, the sisters looked on as Sunset closed the door behind them, and it was here that Twilight took note of their arrival.

"Ah! You're here! Excellent! Please, take a seat."

Whatever it was she'd brought them here for, it was obviously something she was keen on, so, not wanting to disappoint, the three sisters, took their respective seats, sitting in individual ways, from Adagio crossing her legs, to Aria leaning back and folding her arms, to Sonata politely keeping her hands upon her knees. Sunset, likewise, took a seat herself, right next to Adagio. And now, with all of them gathered, Twilight, bearing a wide smile, cleared her throat a little before getting down to business.

"Well, as you probably know, I have always had a fascination with learning as much as I can about your world and those who inhabit it."

There were nods all around at that, prompting Twilight to continue.

"There are just so many things that I could sink my teeth into in terms of some kind of research projects. Things like magic, or the way ponies of Equestria have sentience but ponies of this world don't."

Aria raised an eyebrow.

"Okay, just to be clear, are you going to ask to do experiments on us? Because we usually expect people to take us out to dinner and stuff before strapping us down to anything."

Twilight, perhaps having missed the latter part of that statement, let out a brief giggle, taking a moment to slightly adjust her glasses before shaking her head.

"No. Because for what I've chosen to do research on, I think I have enough information as it is without any physical science needing to be done."

Aria nodded to that, leaning back into her chair and leaving the floor open for Adagio to start taking on a look of interest herself.

"In that case, Twilight...what is your little project about? And more importantly, why are we being asked to hear about it?"

To that, Twilight smiled wider, and Sunset looked away with just as much embarrassment as before, not looking at the former as she answered the question.

"Well, Adagio, it came to my attention that the three of you, the Sirens, are perhaps some of the most unique life-forms that the world of Equestria had to offer."

A look of pride crossed Adagio's face, and she swept aside some of her hair.

"Guilty, as charged."

Twilight nodded.

"That's why I decided to write a paper on perhaps one of the most important aspects of any form of life...reproduction."

Immediately, the room fell as silent as a grave, and all three of the Sirens looked to the former Crystal Prep girl as if she'd just made some kind of terrible joke. But, one look at her face made it clear that she'd meant every word of it. So, Adagio glanced to Sunset, who was currently burying her face in her hands, before then looking right back to the young scientist.

"Um...would you care to repeat that, my dear?"

Still smiling, Twilight nodded.

"My project has been to document and understand the intricacies and details surrounding the mating habits and reproduction cycles of Sirens."

Again, silence fell, and Adagio blinked slowly, still not quite believing what she'd heard. Meanwhile, Sonata seemed less shocked, and glanced over at her sisters before looking back over to Twilight. Then, in a manner similar to a school-child, she raised her hand into the air, catching Twilight's attention.

"Yes, Sonata?"

Lowering her hand again, the youngest Siren spoke up.

"Um...shouldn't you have, like, watched us doing stuff to get this together?"

Again, Twilight shook her head.

"No need. Given everything I've observed about you three, the things you've said and even just looking at your natural Equestrian forms, is enough for me to get a few working theories together."

Here, Adagio shook herself out of her state, raising an eyebrow.

"And when, exactly have you seen our natural Equestrian states?"

Turning, Twilight pointed to one picture in particular upon the board. It was, undoubtedly, the there Sirens' true forms. From the looks of it, it was a picture taken during their failed bid for world domination during the Battle of the Bands. Seeing the picture, the three sisters took on looks of confusion, leading to Twilight explaining herself.

"I came upon that picture and several others in the days before I first started investigating magic here at CHS."

Slowly, and after looking to her two sisters, Adagio sighed, putting on a slight smirk and leaning back into her chair.

"You know what? Go ahead. Let's hear what you have to say. It might be fun."

Her sisters looked to her with incredulity, while Twilight clasped her hands together with glee. After nodding enthusiastically, she got to work, turning back to the board and pointing to one sheet of notes in particular.

"In that case, let's get the first point out of the way. Because from the various pieces of information I've been able to gather..."

She turned to face them.

"...it's inherently difficult for Sirens to actually become pregnant."

Adagio's smile faded, and she started to frown ever so slightly.

"Oh? And what makes you say that?"

Twilight turned to her notes again.

"Your descriptions of your time here in the human world makes it clear that you have had many lovers, stretching back far into the days before things like contraception was widespread."

She looked to Adagio once more.

"Even if the cultures you immersed yourselves in did have some local form of preventing conception, perhaps some herbs or the like, you never actually partook, did you?"

There was a pause for a time, but when it ended, the three sisters shook their heads, and when she saw this, Twilight focused her attention on Adagio in particular.

"Adagio, the longest-lasting partner you ever had was that Prince from a few thousand years ago. And from what you told me, you and he had to be together quite a few times before you actually became pregnant, yes?"

Adagio folded her arms, nodding and looking at least a little irritated over that memory.

"Yes...several dozen times, in fact."

Twilight nodded back.

"This might explain the higher sexual drive the three of you have. On some, perhaps unconscious level, you're aware of how difficult it is for you to conceive, hence your overt and frequent need to find potential mates."

Here, Adagio smirked.

"I prefer to think of it as just us enjoying it. More fun that way."

There was a round of laughter amongst her sisters at that, but Twilight, for her part, did not seem fazed by her remarks. Instead, she turned to yet another set of notes, starting to explain herself yet again.

"The second point I think is worth discussing is that...well..."

Here, she hesitated for the first time, and when she finally did speak up, she looked to Adagio with some measure of nervousness.

"...we should probably discuss...your son."

As before, Adagio seemed surprised by this, though she said nothing as Twilight carried on.

"Forte was half-human, yes. But even so, he's probably the closest there has ever been, or ever will be, to a male Siren. As such..."

She pointed to a few of her notes and charts.

"...I think our understanding of him and the kind of person he was can tell us much of what might have occurred had full-blooded male Sirens existed back when you lived in Equestria."

Adagio considered that for a few moments.

"Yes...I suppose he was."

Giving a short nod to her, Twilight picked up a few sheets of paper, looking over them briefly before getting back to the matter at hand.

"According to what I've learned about him, he was an incredibly protective person, yes? And skilled in combat, despite never having been in a fight before his first?"

Adagio shook her head.

"No. It was...something of a shock for me. To see my son so proficient, to see him so easily take on more experienced fighters. It was...like he was born to fight."

Twilight tapped a pencil against her glasses as she took that in.

"A natural instinct to protect and fight. That sends a very clear message about what male Sirens would have been like had they been around. They would have most likely been like soldier ants, born to safeguard all others in the group."

Adagio frowned slightly.

"I'd prefer not to hear my son being compared to ants, if you please."

Twilight coughed nervously.

"Of course. Although it does make something clear to me."

She gestured to the three of them.

"Sirens, at least the female ones, may well have been the dominant sex amongst your race."

To that, Adagio let out a hearty chuckle.

"Is that truly a surprise, Twilight?"

Twilight shook her head.

"No. But it does bring me to another matter. That being that, in matters of mating, it seems to be the role of the females to seek out and attract a partner, rather than the male."

That caught their interest, Sunset included, and so Twilight began to explain further.

"Your magically-induced songs, though clearly having the side-effect of causing conflict amongst those who hear it, also acted as a lure. A means of bringing others to you?"

The three sisters looked to one another, then, it was the turn of Aria to speak up.

"Yeah...but that doesn't mean a guy-Siren couldn't, right?"

Twilight gave a small smile.

"Actually, it may well do, as your sister..."

She pointed again to Adagio.

"...once said that Forte's own singing was not exactly all that impressive."

Aria turned to her sister, who sighed and gave a short nod of her own.

"Yes. My dear boy had many fine qualities, but his singing was most definitely not among them."

She paused, looking deep in thought, which was reflected in her tone.

"Actually...now that I think on it...Twilight may be right about this. Perhaps males weren't the ones to find mates."

Aria raised an eyebrow.

"Oh yeah?"

Adagio turned to look her in the eye.

"Think about it. We three have never had nay problem in flirting or going out to find partners for ourselves. It was as if doing such things was part of who we are. But Forte?"

She looked away briefly.

"He was never that good at it. Oh, he could swing a sword okay, but when it came to girls, he was completely out of his depth."

A nostalgic smile crossed her face.

"I remember when he first became enamoured with that Princess of his. For all their time together, he never had any sure footing when dealing with her. Sure, he was always sweet, and she to him, but in the grand scheme of things, it was like romance was something he was just...born to be bad at!"

Here, she looked back up to Twilight.

"Colour me impressed, Twilight. I don't think I'd have ever considered this until you mentioned it."

A wide smile plastered Twilight's face.

"Thank you. The three of you have given me a lot to work with during the brief time I've known you. Little details and stories you've told me that have really helped to paint a picture of what really goes on in...well...this particular field of your lives."

A sultry smirk crossed Adagio's own face, and she turned her attention to Sunset, who had been largely keeping silent this whole time.

"I trust you will be her next test subject, Sunset?"

Sunset frowned to that.

"Hardly! If Twilight needs to know about pony mating or the like, there's plenty of books on it back in Equestria I can ask Princess Twilight to send over."

Adagio sighed.

"Hmmm...shame. I'd have liked to see how she figured stuff out with you."

Sonata looked over her sister's shoulder to look Sunset in the eye.

"You know...nudge-nudge wink-wink?"

Sunset rolled her eyes, and Twilight, who had taken a moment to be somewhat amused by this, cleared her throat, gaining their attention once more.

"You know...I've been collecting these and other thoughts oh the matter together if...well...if you'd care to look."

Adagio turned to Aria, then to Sonata, before giving the former Crystal Prep girl a nod and a smile.

"I'd be delighted to see it, Twilight."

Twilight clasped her hands together in a display of joy over that, but had no chance to say anything further for the time being, as Adagio gave one of her customary smirks to the girl.

"Although...if you'd like more detailed analysis of Siren sexual practices, I'd be more than happy to give a demonstration."

Sunset's head snapped in Adagio's direction.

"Adagio?! She's your descendent!""

Adagio frowned to her fellow Equestrian, only to be interrupted when Twilight felt the need to point something out.

"Actually, given the sheer length of time between the day Adagio first gave birth to Forte and the arrival of my generation of her descendants, I'd say enough inter-mingling of other bloodlines has occurred to actually mean that it wouldn't technically be incest at this point."

Adagio, for her, part, looked rather pleased at this news, while Sunset looked to Twilight as though she had just made a terrible error. As for the spectacled girl herself, she paused, taking in what she'd just said, then starting to bear a look of regret.

"Oh dear. I...I've made a huge mistake, haven't I?"