Kazutaka Tatsuji

Asagi Igawa is a veteran Shinobu. After defeating an arch enemy a long time ago, she thought she could finally settle down. Yet, her arch enemy was revived from death through a pact made with the head demon in the city and swearing to take revenge on her by hurting those who are close to her. Her boyfriend, sister (a Shinobu) and her are part of the act being abused emotionally and… sexually…

Kyle, the protagonist of this story, is one of the 7 heroes who defeated the evil overlord. After that battle he starts a conquest of the continent in order to unite the humans who live on it. Standing against Kyle is only his younger brother Syll, who is also one of the seven heroes. Kyle stole his throne, but failed to kill him. One day, another of the 7 heroes appears before Kyle. She is Nina, an elven princess. Kyle knows that Nina and Syll are lovers, and a dark desire begins to burn inside of him... (These OVA's is based on the game by Black Lilith.)