You and Stan have been best friends since you were eight. And he’d always call you and ask to pick him up while he was drunk. And when you climbed back into bed he followed you and that led to kissing that led to your fifth trip to the trash can with him to make sure he made it alright. So here you are standing next to Stan while he vomits for two reasons him being drunk and the fact that when he has any interaction with someone he likes he pukes.