Can't Find It!!!!!

I read this shounen ai/ yaoi (not sure which) where this guy moves into a dorm/house and everyone throws a welcome party and the next morning he wakes up in somebody else's room and notices that there's a guy lying next to him. He also notice that his lower back hurts. In the end it turned out that he was drunk and fell into a bottle or something like that. I can't remember the title or who it was by!!! Can someone help?