Well you are in luck because none of that are in any of Siren's games. He tends to be very vanilla. You won't see any NTR or MMF. You are not going to see the MC sharing with any other guy. The threat may be there, but you won't see a NSFW scene showing that.
In the Zombie's Retreat games, the women who come into contact with the zombies will want to have sex with them. This will go until they are f*cked to death. So the threat is there but you won't actually see a scene like that.