A lawyer named Patrick Smith infamously invited one of his friends to bring his "old horse fat" over to have a three-way with his girlfriend. The email was forwarded all over.
British slang for "dick" or "penis," most popularly used in a workemail written by an international law firm lawyer Patrick Smith (now fired).
Smith in email: "Dude, 'Carol' (not her real name) wants some of that double penetration action, so let me know when you and the old horse fat are around."
Boys who enjoy yaoi (a genre in Japan that contains sexual and/or romantic relations between two men); literally translates to "rotten boy"; corresponding female : fujoshi