Bestiality, tentacles, straight-shota, lesbians... they're all convenient subsitutes; A comfortable way to watch women get aroused without the distracting guilt-trip of seeing a man getting involved. This is just a psychological hang-up I have. I enjoy bestial themes in the same way I enjoy tentacle porn. I don't watch it for the tentacles. I watch it to see a woman get overwhelmed and aroused by something relentless. Their arousal becomes my arousal.
For the longest time, I didn't even realize that I was incorporating elements of this fetish into my works. In my mind it wasn't "real" sex, it was just a girl getting turned on by something.