Not even if I do this?

Vince couldn't believe his girlfriend, Ivy, had agreed to swap bodies with his mom for the week so she could have a break. It was torture watching his mom's body walk around with his girlfriend's mannerisms. She was still very much a flirt and a tease, which was driving Vince crazy.
"How many more days?" Vince moaned as he watched Ivy clean the kitchen.
"Only a few more," Ivy replied. "It's not too bad. She's got a nice wardrobe."
"I don't care about her wardrobe. I'm so horny right now and we can't have sex for another few days."
"Who says?" Ivy smiled.
"I'm not going to fuck my mom."
"Oh? Not even if I do this?"
Ivy hiked up her skirt and rolled her panties down her legs before kicking them off. Then she bent over to unstack the dishwasher. Her skirt rode up her wide thighs, nearly revealing Vince's mom's big butt. She giggled and looked back at him, biting her lip and wiggling her plump, jiggly ass.
When she stood, Vince couldn't take it anymore. He dropped his pants and took her up against the fridge. Spreading her fat butt, he thrust his cock in between her thighs, his cockhead sliding up against her clit. She moaned as he thrust against her, lubricating himself on her juices before sliding into her warm, welcome hole.
His mom's body was deliciously wet, and Ivy quivered around him, moaning as he fucked her hard, watching her fat butt bounce until he thrust in deep and came, his cock throbbing into her pussy, emptying his seed into his mom's cunt as her body orgasmed with him.

A college student finds an experimental device that allows him to possess his girl friends in Role of a Lifetime, available on Smashwords and Amazon. Preview here.