Yu Yu Hakusho
A anime/manga series that follows Yusuke Urameshi, who dies, becomes a ghost, comes back to life and become a spirit detective. Fighting various powerful demons and to save the world.
Byakko, the White Tiger
During the Spirit Dective/Maze Castle Arc, Team Urameshi had to fight Byakko. A man-tiger demon who could absorb energy and grow bigger, stronger, and fatter until he pop like a balloon and/or exploded.