The idea of having a gun that cause a girls breasts to grow...just by pulling the trigger. Jesus Christ, the thought alone sends a tingle of pleasure through you. As you sit there and look at the device, well...you imagine all sorts of ways of using it. You could use it on your sister - get some revenge on her by making her breasts grow so large she wouldn't be able to leave her room. But that could lead to some awkward questions. You could try using it on your pregnant cousin, but the results from that wouldn't even be made apparently until over a decade in the future...
Really, the best and only option was to take it to school!
You're a junior in high school. You should be able to use it covertly at school and really see how powerful this thing is - there's plenty of hotties just waiting for an increase in breast size. Hell, maybe you could even charge for the service. Girls would probably be lining up around the block for a chance to have bigger tits. Their boyfriends certainly wouldn't mind. You go to sleep with a smile on your face, imagining the possibilities.
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The next day finds you riding the bus, the device concealed safely in your backpack. You casually scan the others on the bus - there's plenty of possibilities around you...Sarah, the cute sophomore with an already sizable set of knockers...Jenny, the senior cheerleader and resident Uber Bitch who most people couldn't stand...Emily, a shy freshman who had the most incredible body of anyone in the school but didn't seem to realize it...
But you manage to control yourself until you get to school. No need to jump the gun - so to speak.
You keep an eye out for the first few periods, wondering who to use it on. A test run is probably in order, just to see how well it works. So, in English class, you covertly take the device out and aim it at Bethany, a cute junior girl sitting next to him. A quick squeeze of the trigger while aimed at her has you holding your breathe.
Bethany gasps and looks down, drawing a few confused stares from people around you.
"Sorry...sorry...dunno what came over me," Bethany muttered, looking down.
Your pants are uncomfortably tight - because right before your eyes, with a simple squeeze of the trigger, you saw Bethany's breasts go up a cup size. Even as you watch, you can see Bethany looking incredibly confused - though not especially disappointed - as she examines her newly expanded chest.
Finally, gym class comes around, and you can no longer resist the urge to really try it out. You finally settle on Ashley, a sophomore girl with a mostly flat chest. She'd been a crush of yours for the past few months, and she was generally pretty friendly. A nice jump in breast size would definitely benefit the girl, and you were only too happy to provide it for her.
Before the class gets started with running laps, you discreetly manage to aim the gun at Ashley and pull the trigger, holding it down firmly.
The effect is more than you could've expected or hoped for. In a matter of seconds, Ashley's tits burst out of her shirt and bra - sending them flying across the room. A shrill scream of terror, sliding into gasping pleasure, fills the air as Ashley's chest grows so fast that she finds herself being yanked up off of her feet, dangling from tits that suddenly rival the size of the bleachers themselves. Gasping with disbelief and pleasure, you watch as her breasts continue to swell up, shoving people away with their sudden growth.