Emily pushed open the science lab door with enough force to make the hinges groan. Behind her, Jessie juggled two overflowing notebooks and a backpack threatening to burst at the seams. "You didn’t have to slam it," he said, adjusting his glasses. The lab door swung shut with a soft click—almost apologetic compared to Emily’s exit.

The girl smirked, flexing her fingers absently. "Didn’t have to. Wanted to." Her voice carried a new, effortless confidence, low and smooth where it used to crack with nerves. Emily's plaits swung with her usual brisk stride, but everything else about her movement screamed different—controlled, deliberate. Jessie blinked as Emily adjusted the straps of her backpack—the kind of motion that made the seams of her top tug dangerously across exposed shoulders that now carried the definition of someone who could probably bench press Jessie over her head without breaking a sweat.

Emily's transformation was no secret; she had spent sleepless nights mixing and perfecting a formula that was supposed to be perfect—a precision blend of protein catalysts and muscle growth inspired by those pulp sci-fi novels Jessie would sneak into chem class. But when the new girl Zoie came with the same project and called her "tiny", Emily snapped. Sure, testing the formula on herself was reckless. But it worked too well - her body responded with terrifying speed—muscles expanding rapidly, fat redistributing into dense tissue, even subtle hormonal shifts (hence the breast growth). Three weeks ago, she couldn't have lifted a full beaker rack without both hands shaking. Now? She'd rearranged the entire lab equipment storage solo before second period.

The hallway fell eerily quiet as Emily strode forward, her every step a deliberate thud of authority. The floor shuddered under the girl's weight—not that she was heavy, exactly, but the sheer density of her frame made every step sound like a declaration. The fluorescent lights glinted off the sweat-slick curves of her biceps—veins beneath her skin stood in sharp relief, straining against the taut flesh that stretched over every corded muscle.

Her clothing seemed to cling to her, surrendering meekly to her powerful form. The seams of her top, along the back, tensed with every flex of her lats—a constant, rhythmic tug on the fabric. Her chest strained against the constraining cloth, emphasizing the soft, round shapes of her breasts. Her shorts left little to the imagination, the denim straining to contain her hips and rear—which had widened significantly to accommodate her now powerful thighs. Her abs, toned and firm beneath smooth skin, flexed faintly—an unconscious display of power that made Jessie's throat go dry when he accidentally glanced down. The girl walking ahead of him had same freckles, same fiery red hair, same sharp green eyes framed by glasses that burned with quiet, confident pride, but the way she carried herself—chin high, shoulders square—was almost unrecognizable.

Jessie cleared his throat as they rounded the corner toward the lockers, his fingers tapping nervously against the side of his notebook. "So, uh," he started, then hesitated, glancing at Emily's profile—the sharp line of her jaw, the way her neck tapered into newly defined trapezius muscles. "You haven't had any... weird side effects, have you? Headaches? Muscle soreness?" His voice dipped into a whisper on the last word, as if mentioning the obvious might offend her.

"Hmm... Nope. No side effects." She flexed an arm, her bicep bulged impressively. "Only gains." The corners of her mouth curled into a smirk—one Jessie would recognize instantly, the same one she’d worn during their late-night chem sessions when a stubborn equation finally clicked into place. But this time, there was something else lurking beneath it—a quiet, almost predatory satisfaction.