Dan figured he didn't have much to lose, it was probably nothing special anyways. He might as well try it out and see if it did anything to him, he might as well gamble on his cock. Maybe it would make it bigger! Dan took the bottle upstairs to the bathroom, and closed and locked the door. He stripped off his pants and underwear, leaving the rest of his clothes on, and examined his cock.
At the moment it was soft, but he had an average cock for a boy his age. A bit more than five inches long and a set of balls to match. He looked from his crotch, to the bottle, and back again. "Well, I might as well give this a go then." It was weird holding the bottle level so that he could aim it at his crotch, but when he did he pulled the trigger on the spray bottle, coating his dick in the substance.
It felt cold, like a regular aerosol landing on his skin. But then it started to sink into his skin and his whole groin area felt warm. Dan gasped and set the bottle down on the counter, leaning back against it as he watched his cock get hard, standing completely erect as the heat grew and grew.