I actually lose the ability to get a hard on if the story is TOO good. Like if a story is about rape mostly then if the text is in all gibberish and japanese then I can fap away no problem because it's still hot and I don't really feel anything for the characters.
For stories I DO understand though, it's usually a bit harder because I generally know what's going on, so stuff like NTR and rape starts to get to me more often.
It's even worse when the story is really really good and you feel emotionally invested in those characters. Like when a main character gets her life ruined (and you recently discover that from translating the dialogue) and you literally cannot do anything but stare as your john swings loose and you find yourself immersed in the story but repelled from playing it for any of its H-content anymore.
But maybe that's just me