>>47809821) my dick reacts to it
That should be enough explanation but Ill try to rationalize it
2) Every girl takes the dick in her pussy, of course an anime girl will save it for someone special, but how many take it up their butt? A girl who is willing to indulge in a taboo is just sexy
3) seeing a girl like something she isnt supposed to like a as a proper girl is hot
4) works good with corruption, a girl understands her pussy gets sullied and might accept she is going to cum from it, but having her butt taken and then having it feel good makes her question herself more.
But yeah mostly point 1
