The first Japanese heel wrestler appeared in Japanese professional wrestling. He was Tiger Mask who had been called yellow devil with fears in the United States. He was the first masked wrestler, and he fought cruelly breaking the rules. But he had a secret that he couldn't talk to anyone. Date Naoto, who was Tiger Mask, had been raised in a orphans' home, then he had been trained by the heel wrestler training organization, Cave of Tigers. The wrestlers who had trained at Cave of Tigers had to pay a lot of money. However, he knew that the orphan's house was suffering from a lot of debts, and he took over the debts in order to help Ruriko who was his childhood friend and the manager of the orphans' house without revealing that he was Tiger mask. Thefore, he couldn't pay money to Cave of Tigers. Furthermore, he quitted his villain acts for the children who yearned for him. Because of the betrayal, Cave of Tigers began to send heel wrestlers one after another to destroy his carrier as a wrestler.