To be obsessed with the male genitals.
To have a burning need to have to bring the following words penis, cock, dick, schlong, nob, skin-flute, pork-sword, shaft, pipe, pole, meat etc in to every conversation even if it's not appropriate in any way or makes no sense to do so.
Luke: Kyle, have you done that job yet?
Kyle: No but my dick is reallyhuge.
Luke: You really need to deal with your nobsession.
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