I'm careful about recommending tag search, but the incest tag is among the tags that may actually get you useful results.
Hypno Training: My Mother And Sister may be the closest thing to what you're looking for. The protagonist uses hypnosis to render his mother and sister helpless. While they can't do anything about it, they are still fully aware that they are raped by the protagonist.
Lust and Power: The protagonist protects his mother and sister from demons, but demands their sexual services in exchange. He doesn't rape them in such a cruel way as the protagonist in Hypno Training, but it's still very clear, that they are not happy about their situation.
After Invasion: In a dystopian world, the protagonist has aquired wealth and power and now comes home to mother and sister. She or he immediately shows them, who's in charge. No rape, but domination and spanking. My personal favorite, because with a female protagonist, there is hot lesbian action.
Snow Daze: The protagonist manipulates his mother and sisters into becoming his harem. Domination and mind control. Great artwork and characters that are actually characters.
Fate of Irnia: The protagonist inherits an artefact, that lets him corrupt women. That way, he can either enslave or romance his mother, sister and aunt.
