This is not just a brain fart. This is ass-flapping mental diarrhea.
This level of absurdity defies adjectives. Sure, masturbating to Gay porn means you're gay, but masturbating to straight porn means you're straight. It really isn't that difficult.
Aside from that, homosexuality has nothing to do with animal rape. Also, it's implied here that the AIDS came from the animal, which is a huge biology fail in and of itself(in most cases).
Lastly, assuming this was true for a moment, WHY THE FLYING FUCK ISN'T EVERY PERSON ON THE PLANET A HOMOSEXUAL ANIMAL-RAPING AIDS INFECTEE YET!?