Maybe later

"Hmm," Zoe muses making a great show of pretending to think about it "there is this toggle switch thingie here on the butt. I bet it's a reverse mode of some kind. I could probably use it to change you back..."

"Come on Zoe quit screwing around" you demand while desperately trying to wrangle your new tits back into your top "Just change me back and I won't say any more about it. I'll even let you keep the gun just promise not to use it on me again."

"Oh I'm keep this," she laughs brandishing the ray gun like a wild west gunslinger "but I'm not turning you back into my boring big brother. Not yet anyway. First you are going to have to do something for me..."