(insert *NSYNCer here) catches Justin jerking off (in the Quiet Room, perhaps?) and makes him finish while he watches.  They can be in a relationship or not.

I'd love some threemanbus. It doesn't have to be sexual, though I certainly wouldn't complain if it was.

Thank you in advance :)

One bus talking about what's going on on the other while they're on the road overnight, please.