Character Description: Royakan
Royakan is a demon of hell, but is a gentle demon until Naraku put a jewel shard on his forehead (eyes turned red). He starts looking for InuYasha, and in Episode 20: Despicable Villain! The Mystery Of Onigumo and Episode 21 Naraku's True Identity Revealed, we see what happens especially when Royakan didn't want to be sucked into Miroku's wind tunnel. Royakan can also spit wolves out of his mouth.
Royakan comes back when the panther tribe came back. He wants to help Sesshomaru, but was denied. Also he tells Koga, Ginta, and Hakkaku what happened 50 years ago when the panther tribe came back. The story 50 years ago was Royakan and other demons were in debt to Sesshomaru's father, who killed the leader of the panther tribe. They fought the best they could, but retreated.