Coochie Coochie Coo is usually used by parents when tickling their newborn child.
Upon tickling and saying "Coochie Coochie Coo" to the child, they will most definitely either start laughing or crying. It depends on how understanding your newborn child is.
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