No way

She gives a disgusted look, “No way. You’re his brother. That’s like incest.”

You say, “I wouldn’t be fucking him. I would be fucking you.”

She shakes her head, “Yeah, no. I don’t even want to think about it. Brothers smacking their balls against each other. Ick.”

“Our balls wouldn’t be touching,” you try to explain.

“Eww you’re looking at your brother’s hard dick right now.”

It’s difficult not to look. He’s stroking it.

“We’re both attracted to you. Not each other.”

Your sister-in-law shakes her head, “You guys just want an excuse to fuck each other.”

“What!? No!”

She laughs, “Fine. I’ll give you want you want. Suck your brother’s cock. Then you can do whatever you want to me.”

Your brother stops stroking, “What the fuck? No!”

You look from his cock to her perfect rack.

It might be a fair trade.