Mike immediately realizes the magnitude of his error in judgement. The moment he touches the giant girl, she sharply flinches, a massive movement that startles Mike even more than her. As she jumps away, she turns her massive head around and back down to stare directly at him. Her mouth drops open in shock.
Mike’s first reaction is to grab the gun and enlarge himself. He knows he has to flip the switch to “grow” pretty much instantly and manage to hit himself, and even then he’s a normal-size guy in a sorority house. He can handle that later, but what he can’t handle is what actually happens. The titanic young woman grabs Mike with a giant hand that bursts out like lightning, leaving him with no time to react before she lifts him up to about a foot and a half off the ground.
"Oh my god, look at this," she says, as she spreads Mike’s arms and legs to examine him. He tries but is powerless to resist. All the girls stop watching the movie and lean over to look at him as his arms and legs are forcibly spread to the side. "It's real. It's alive."
"Who are you?" she says, but before Mike can answer, the gun is knocked out of his hand. He had been fortunate in his earlier transformations that the gun had been designed to change size along with him, but now Mike sees that the gun also resizes itself in alignment with whoever's holding it. So, as the gun falls into this girl’s giant left hand, it enlarges to fit her size. After a moment of initial shock, she quickly recovers, gripping the gun and examining its controls.
"Oh my god, this has shrinking... growing... transformation... mind control?!?" She pauses, and looks back at Mike in her other hand. "And it obviously works."
"This is amazing," she says. "Actually, you know what?"