He has a girlfriend (but she's very understanding)

Mike's apartment was a small one-bedroom off campus above a sandwich shop. When they got inside, Mike slipped off his shoes so Amy did the same. Then he called out.

"Rose! I'm back. And I brought you a present!"

"Huh? Whose Rose?"

"She's my girlfriend. But don't worry, she's cool."

Rose appeared in the living room a moment later. She had died black hair that was shaved in the back and sides, a multiple piercings in her nose, lip, and ears, and a tattoo of a blossoming cherry tree that ran from her left ankle all the way to her hip. Amy could see this because Rose was wearing a black tank-top and a pair of high-waisted black lace panties.

Rose seemed totally unembarrassed by her lack of clothes as she gave Amy a look up and down and introduced herself.

"Oh, hi. I'm Rose."

"Amy." Amy said. What the fuck is going on here, she thought, I was supposed to suck him off for my dare, but his fucking girlfriend is here!!

Mike settled the matter instantly. "Amy here wants to give me a blow job to settle a dare from her friends."

"Oooh, kinky," Rose said, "I think I'd like your friends."

"I..I uh. Sorry, I didn't know he had a girlfriend. I'll just..."

"Hey, don't worry about," Rose said, "I'm totally open to share Mike's beautiful cock with the world--as long as he's honest with me. Right Babe?"

"Yeah, we don't really subscribe to bourgeois, heteronormative notions of 'monogomy'." Mike said.

"Oh," Amy said, "that's really cool. So that means you'll let me...you know, do that think with Mike? For my dare?"

"Well, I might make some conditions..."