A term used for somebody with the absolutely grossest hands. Nastiest shit, you don't want to shake hands with them, commonly used with people who chew their nails and or pick their nose
Guy 1: *picks nose* bring it in for a handshake.
Guy 2: hell no get those musty mikes away from me!
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