Ryuo Taro was born from dragon and human parents. His father, Wadatsu Saburo had to live in hiding by Ushikubo's trap. One night, Saburo met a woman named Katsura. She became his wife and then had a son named Ryu Maru. Katsura belonged to a dragon family that was destroyed by Ushikubo. Saburo found out about Katsura's true identity and then Katsura left. After Ryu Maru grew up, he changed his name to Ryuou Tarou Masatatsu. He swore to avenge his parents by attacking Ushikubo.