There are some rape scenes where you may or may not wannt to interrupt before something happens and there's quite a bit of sharing going on (at least one scene isn't avoidable as far as I'm aware). I think all in all we are talking about 5 ot 6 scenes in total.
actually, storywise it's best to actually save the 2 girls about to be raped (you can watch the scenes using spirit potions)
-you get to share gwyn 2 times; once to progress with Alice and once to help Victoria
-there's shakala and the sharing is unavoidable
-you share ziva 2 times; one is avoidable but it requires you to fight a tough boss and since he still gets to fuck her it's not worth it, the second one is unavoidable, but at least you get to doubleteam her
- you get some netori scenes with Maghda and Victoria
and here's where the issue with Caleah starts, if she's to become an acolyty of the titty-hoe aka Quetsh, does that mean we'll be forced to see her fuck other dudes and pilgrims?