So far it's only sex with the MC. There's some very light "rough" sex later and some hard spanking, that kinda thing. But the sex sticks to being pretty sweet all things considered. Two of the girls seem to be out and out virgins with almost no experience. While a couple others are much more confident in demanding what they want.
There are horror moments in the game. And Caribdis does not hold back on the gore when a violent situation arises. But it never intersects with the erotica. Which isn't to say pretty characters won't ever be hurt. Caribdis seems to be an equal opportunity body mangler.