An anthro macro snippet with Cadence and Shining Armor at the beach, please? Cadence asks Shining to lather her up with sunscreen. What he doesn't know is that it has a growth formula mixed in.

“How’s that, honey?”

Cadance groaned quietly. “Mm.”

Shining chuckled. He was crouched over Cadance’s back, one foot on either side of her. Around them, the sounds of the beach filled the air: crashing waves, shouting kids, chattering gulls. “Sounds like you’re enjoying this as a little more than just a safety measure.”

“Can I help it if my husband has magical hands?” Cadance smiled to herself. She spread her legs a little wider on the towel, careful not to let any sand get on. Her belly felt warm, and her back even warmer.

She groaned again as Shining’s masterful hands massaged her right shoulder. Officially, he was applying sunscreen to her - she’d always burned easily, and wanted to be able to enjoy her vacation without getting an itchy, peeling coat. Unofficially, she just loved letting him touch her - all of her - and in public, too. She’d been sick and tired of all the “propriety” that came with being the Princess of an empire. She was the alicorn of love, dammit!

And then, un-unofficially… A certain Twilight Sparkle was currently holed up on a sand dune a few hundred meters away, bearing a beach chair, a pair of sunglasses, and a set of binoculars. She had her eyes fixed on the bottle of sunscreen. She had plans - and it looked like the happy Royal Couple was playing right into them.

Cadance groaned a third time as Shining’s hands moved down to massage the sunscreen into her lower back. “Shiny, that feels good.”

“Okay,” he said. “Now you’re definitely enjoying this too much.” But he didn’t stop. If anything he just rubbed her a little harder, a little deeper.

Meanwhile, the potion that Twilight had left in the sunscreen went to work. Cadance squirmed atop her towel as, slowly, her body began to grow. Her limbs grew longer, her shoulders widened, and even her chest began to swell until her already-generous breasts had pushed her chest a few extra inches off of the ground. She just groaned, too lost in bliss to be concerned with a few extra inches.

It wasn’t until Cadance’s rear started to fill the space between Shining’s legs that he noticed the changes. He’d been crouched down on Cadance’s thighs, leaning forward and totally focused on his work, only pausing every so often to squirt another dose of lotion onto his palms. But as Cadance passed six-foot-six (from a previous height of six-foot-one) and hit just under seven feet, Shining had no choice but to take note of the wobbling, generous ass that was now growing and grinding against his crotch.

“Uh,” he said dumbly. “Honey?”

“Keep going,” Cadance mumbled.

“But - “

“Keep going,” she insisted. Shining just flushed and went back to work.

Back in the sandbar, Twilight had her right hand somewhere in between her legs. Her left held the binoculars up to her eyes so tightly that it might as well have been screwed in place.

Cadance had stopped inching, and was now definitely growing. She squirmed and moaned, flexing her lengthening arms every so often as she passed seven feet, still lying down. Shining, preoccupied with rubbing, found his blush spreading across his cheeks as Cadance’s whole body grew larger, curvier, and even slightly more muscular beneath him. The second Cadance hit eight feet - which was, coincidentally, the instant that a nearby couple took notice of the growing alicorn - Shining’s swimsuit began to strain against his raging, hardening erection.

He started to thrust his hips a little bit, really grinding his package against Cadance’s larger - and growing - ass. He didn’t really have a clue what was going on, but whatever it was, he’d long since decided that he liked it. By the time she hit nine feet, only his toes were still in contact with the ground below him.

“Feeling a little frisky, huh?” Cadance mumbled, grinning. With a grunt, she slowly turned over - and darted to catch Shining as he fell off of her thighs with a shriek.

“What the - ?” She looked him over, blinking. Maybe it was the fact that he suddenly seemed much smaller. Maybe it was the fact that she’d caught him in two hands, and was currently holding him just inches above the ground while sitting down. Or maybe it was the fact that she could only see the upper two-thirds of his body, with her newly magnificent bust more than obscuring the rest.

She blinked again, and then scowled playfully. “Twilight?”

Shining shrugged innocently. “Your guess is as good as mine.” The bulge in his trunks was more than just noticeable by now. If Cadance had to, she would’ve guessed that all thirteen inches of his stallionhood were straining and pushing against that poor little waistband. Then again…

She glanced down at herself. Sure enough, her bikini was more than ready to snap as well, having stretched far and thin enough that it seemed to cover her fist-sized nipples and private parts and just about nothing else. She carefully set Shining down on her lap - he looked so tiny and adorable like that, especially now that he was only two-thirds her size - and peered down at him over her big, round breasts.

“I’m guessing it was the lotion?” she said. Shining nodded. A smile spread across her face. “Well, why’d you stop?”

Instantly, the blush was back on Shining’s face, accompanied by an ear-to-ear, wavering grin. “Keep going?”

Cadance took both of Shining’s wrists in her hands (which was now laughably easy, her much larger fingers encircling his entire arm with little effort) and pressed his hands against her bouncing boobs. She grinned as sultrily as she knew how. “If Twilight wants a show, then let’s give her one.”