When your having sex with a girl and she starts menstruating and you pull out after leaving a load, and the semen and menstrual fluids start coming out and mixing together making this dirty ass goop.
Also used after calling a guy, usually Korean, Semen. When his name is Simon. It is to take it to a 2nd level of name morphing
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