Aku no Onna Kanbu - Season 1

Based on an erotic game by Lune. Katsuma serves as a go-boy for his female superiors and consistently loses his battles against the hero Silverstar. After another such confrontation, his bosses trap both Katsuma and Silverstar. He awakens to find himself under the care of Maria, a different Silverstar. Drawn to her kindness-or perhaps simply taking advantage-he engages sexually with her. This act grants him a special power. With this new ability, he resolves to seek vengeance against his bosses.