Amanda waited till gym class to blast Sarah with the gun. After doing their usual routine (which was much easier with her enhanced physique) the girls retired to the locker room to change. When Sarah had her back turned to Amanda, standing there in only a bra and panties, Amanda quickly took aim and fired, expecting Sarah to shrink into a little weakling.

Something went wrong through. Instead of shrinking, Sarah grew...massive. She let out a gasp as her bra and panties suddenly felt tight against her body. Looking down, she saw that her once toned abs had now turned into a solid six back, becoming more and more defined by the second. Her biceps swelled, inflating and hardening. Her back seemed to expand like a cobra hood, growing into a solid wall of muscle. Her thighs grew huge, becoming ripped bundles of muscle. Her height increased as well, and she grew to easily 6'5. Her breasts exploded out of her bra, about the size of basketballs and standing out proud and firm, supported by thick pecs.

When Amanda finally snapped out of her shock and took her finger off the trigger, she let out a soft gasp of horror and awe at the now gigantic Sarah who stood with her back to Amanda, gazing down at herself, transfixed by her own body.

The other girls in the room could only stare with their mouths open, unable to believe the sight before them. Sarah slowly turned to face the crowd, completely naked and seemingly uncaring. Her body was unreal, muscles huge and ripped, with veins tracing patterns across their surface. With every breath, her cobblestone eight pack tensed and flexed and her breasts jiggled ever so slightly.

One of the girls spoke up, "Sarah! Oh my God are you ok?!"

Sarah smiled, running a hand across her rock hard abs, "Holy fuck....I feel amazing...look at me. Such power...more than I could have imagined."

With that, she began flexing her muscles in turn, running her hands over them. The girl continued to persist, "Sarah what happened to you?! Do you need a doctor?" Sarah slowly sauntered towards the girl, a confident smile on her face. She walked right up to her, till the girl was eye to nipple with Sarah's incredible tits.

"Does it look like I need a Doctor? I don't know or care what happened to me, all I know is my body is perfect, I'm perfect. I've never felt better in my life! Things are going to be different around here from now on. I'm the queen bitch now, and you'll all do as I say! Does anyone have a problem with that?" She snarled, flexing her biceps menacingly. No one spoke a word.

"Good girls, now, what to do next?" She asked teasingly. Amanda stared on in horror at the muscle bound bitch she had created.