The inconsiderate asshole who is to be blamed for everything that goes wrong in your life.
I wanted to fry up some eggs and bacon for breakfast today, but Yesterday Me decided to eat the hole goddamn fridge empty.
Guy 1: You know that psycho chick i finally got rid of a couple weeks ago?
Guy 2: Yeah?
Guy 1: Well Yesterday Me thought it'd be a laugh to call her up and go sleep with her. Now i'm stuck with her. Again!
Guy 2: Man, i really hate that guy!