I'm gay, I assumed that was obvious from my first post in this topic

(and from earlier if you've watched my religion-pots).
Yaoi = It's basically boys love, romance manga/anime made by women, for women. I think what morningstar is refering to is bara. And bara is NSFW.
Fangirls are usually followers of for example an anime character (Take Ichigo from Bleach, he's gotta have some of them). The stereotype is someone screaming of a the subject like regular girls scream at rock stars.