An acronym for "Bhad Mein Jao" widely used by South Asians when they don't have any suitable response for something, means "Go To Hell." Or "Get The Fuck Over" in some cases.
BMJ is when you get a blowjob from someone who has TMJ (Temporal Mandibular Joint) disorder.
The "popping" noise of the jaw common for individuals suffering from TMJ help stimulate through small vibration and pleasurable sounds to quickly bring about orgasm.
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