black_squall's recent request reminds me of one particular story, but I can't remember the title or author. Perhaps it will ring a bell for one of you.
Remus's wolf side is in search of a mate. He's sleeping his way through Hogwarts but never sleeps with anyone twice (the wolf only needs once to decide if he/she is the one). Sirius hopes to be the one, but Remus won't give him a tumble. He doesn't want to hurt Sirius by sleeping with him and then dumping him. Sirius decides that if Remus can't be convinced, he'll convince the wolf to give him a try. He waits until just before the full moon, and then he tries to seduce the wolf by showing him his throat, behaving submissively, etc.
Thanks in advance!