In particular, since Bakker likes the psycho-sexual stuff, I'd point out that there are species even on Earth where rape is the reproductive norm. If that's a sin, and something like that has a soul, it's screwed.
I wouldn't be surprised if the Earwan metaphysical concept of rape wasn't different than our own anyway. As misogynistic as that world is, I'd imagine they'd laugh at the idea that, say, a husband could rape his wife under any circumstances.