The upstairs Bedroom

You all run upstairs, and move into Mary's room. You all kick off your shoes so as not to get the bed dirty, and hop on.

"So Mary, how are we gonna do this thing?" Asks Katy, sliding dowb her shorts.

"Well, I think he's rarin' to go at whatever hole we throw his way. The question is, which one of us should go first?"

You suggest flipping two coins: one to see which hole you'll fuck, and one to see which girl you'll fuck. Heads for Mary, and, on the other coin, for pussy, and tails for Katy and ass.

They agree with your suggestion, and you flip.