Shimai x Saimin: Zettai Fukujuu, Ore ga Zutto Ou-sama

Based on the erotic game by POISON.

Ken, who studies psychology at university, lives his life being despised like dirt by his older sister Sayaka and younger sister Reika. One day, he brings home some "hypnosis cards" that he has been researching. When he combines the "symbols" depicted on the cards and show them to someone, they will enter a trance state, allowing him to control their subconscious. When he uses them on his sisters, they fall for Ken's nonsense and open their bodies to him!! Grinning, he begins to play with the busty bodies of the two girls as he pleases...

(Source: Parabook, translated)