- Naoto Date (Wentz Eiji “WaT”) is a 13-year-old orphan, who lives at an orphanage called “Children’s Home” with the Principle’s 13-year-old daughter, Ruriko Wakatsuki (Watanabe Natsuna) and other children. Unfortunately, the orphanage was going to be shut down due to an outstanding debt. Before that, the Principle brings all the children for one last trip to the local zoo. Naoto and Ruriko stop in front of the tiger enclosure, where Naoto makes a vow that he’ll one day become as strong as a tiger. Later, he has meets the mysterious Mister X, who promised to train him to become stronger, and bring Naoto to a place called “Tiger’s Lair” for training and lives at there. At “Tiger’s Lair”, Naoto has accepted a variety of hard training to become a professional wrestler. When Naoto had grew up, Mister X has granted him with the Black Tiger Mask. Naoto wearing the Black Tiger Mask & golden armor, he becomes extremely vicious in the wrestling ring. He was soon becomes popular with his skillful techniques. In Naoto’s mind, he has not forgotten the orphanage “Children’s Home” which adopted him in his childhood. After Naoto became fame, he had donated his huge sum of rewarded money to support “Children’s Home”. In the meantime, Naoto was surprised to find himself was involved in the illegitimate organization’s money disputes. How dangerous is he to get rid of it? What are the challenges he will encounter next?