There was this black-and-white manga I read where the MC is a virgin loser who makes fantasy video games, and the girls in his video game appear in real life and rape/have sex with him, because apparently he has the spirit of some evil sex god in their world.
The first/main girl was a succubus I think, or in any case a demon girl who didn't understand affection. The second girl was a paladin/knight who tracked down the MC in order to vanquish the evil rapist tyrant, but first she rapes him and then I think kinda gets distracted from her mission. The third girl was made of water.
Can't find this one anywhere.