Billy watched as his friend jerke his cock.
It was indeed turning dark... dark green.
Jerome was too high to notice that his cock was changing. It looked like a pickle now with a mushroom shaped head. Billy's grandma walked into the livingroom and saw Jerome.
"Oh dear! It looks just like the one on the plant!" she said with great concern, "You didn't drink any of that, did you Billy?"
Shocked by what he was witnessing, Billy shook his head numbly and never took his eyes off the changing cock.
With a huge grunt, Jerome shot his load all over himself and then passed out, with a smile on his face.
He was covered in his seed; his cum wasn't white, though, it was green and looked more like lime yogurt.
"Billy, you didn't drink any did you?" the old lady asked again.
"Nah, grandma, Jerome drank the whole thing before I could get any." the young man said. "What's gonna happen to Jerome?"
"I think the best thing for him is a planter and a nice spot in the sun." the old lady said. "Help me get his clothes off and then we'll plant him."
Billy stared at Jerome, his skin was turning green where the thick green cum had splashed on his skin.
"We'd better use gloves, Billy, you don't want to get any of his seed on you or you might end up like him." the old woman said.