It's cute guys, who love each other, who twists the mind of innocent girl to the point, when the girl start to identify with them. There are even two types of FtM people -- one is lesbians, who found it easier to be a straight men, and AAP paraphilicas, who just get off on their fantasies -- the mirror of Blanchard theory.It's anime.
I've seen women and girls alike get so morbidly obsessed with yaoi that they can't bloody conceive love and romance with a female person at all. This probably helped fuel the depression and romantisexual stifling of my now-ex best friend, who almost decided she was trans because of it.
It's all based on idea, that there is one single factor, which corrupts otherwise normal man or woman, and all attempts of building such theories grows from desire to find and, if possible, eliminate this factor. To make the gender binary great again. In this case, it's all about cute girls and boys from anime.