You're missing one important variant: they just don't care. Not "hentailand logic" where your trophy wife mother doesn't wake up from dry anal and complains about a sore back the next morning, but where the other characters do bring it up. The perpatrator doesn't have any fetish for sleep rape in particular, they just don't care either way. Honestly that seems like the most realistic option.From the way i see it there are 2 ways to deal with sleep sex and not have it be stupid.