The boy watched with wide eyes as the girl stumbled back after being struck by the ray. In surprise, he dropped the gun, almost forgetting about it entirely. Other people in the park had turned to look, confused at the sudden burst of light and the scream of surprise the girl had given off. Her friends caught her before she fell to the ground, including his sister. His sister was a sophomore in high school, and had been hanging out with some of her friends - the boy didn't know who they were, since they barely paid him any attention.
The girl suddenly let out a long, sensual moan, prompting startled questions from the others standing around her. She shook her head slightly, but couldn't seem to respond. The others gently set her down, and the girl moaned again, leaning forward and grasping at her chest.
Then, right before the boys eyes and the rest of the people in the park, the girl's breasts began to grow. The boy's mouth dropped open - and he was hardly the only one. Even his sister was staring with wide eyes, backing away slightly from the moaning girl on the ground. It must have felt good, for she let out another moan as they began to increase further in size. In a matter of moments, they had increased several sizes more, making her shirt looked as though it had been stuffed with balloons.