This was a large novel that was both about two men’s bullshit (one is a politician? the other is some kind of professor? they both sleep with the same woman?) and also about a literal angel who causes world war 2 (among other things) in order to engineer…some kind of divine event? the two plots are connected. at some point the world’s most uncomfortable sex scenes occurs when one of the men sleeps with the woman’s mother and her cervix grabs him.
Lost Classics of Teen Lit: Name That Book! 