>>40738471UMMMMMMMMMMM.
Whomp is about the author's fiction suit, his video game playing girl roommate, and the physical manifestation of his muse. The humor primarily comes from the fact that the fiction suit of the author is very self loathing, and instead of being a trumped up mary sue is a sorry guy doing the best he can (like most of /co/)
Playing with the trope of guys like that having "hot supermodel girlfriends...who live in Canada" Ronnie has just that, a hot supermodel girlfriend who lives in Canada. She really likes fat shy guys. In the previous strip she left Ronnie for a fatter, shyer guy.
All from memory, hope that works for ya!