ONI: Road to be the Mightiest Oni

Break your enemy's heart to reclaim your pride. Kuuta, a demon, once challenged a man to a battle and was defeated. At last, he arrives at Kisejima Island. He and his partner Kazemaru, whom he met on the island, overcome their ordeal as one, gaining new strength along the way. This time, will the duo be able to achieve victory? Join Kuuta on his adventure to get revenge against Momotaro, a demon masquerading as a man.