Takenaka Hisashi was first introduced in the manga when he was a third year in high school. He first appeared when Minoru, Seiji, and Hayama were on the promotion exam.
Takenaka was part of a boxing club back in the Kunitoyo Academy High School. He was initially arrogant especially towards Minoru. During the promotion exam, he fought Minoru using prohibited attacks, like punching him in the face, which was not allowed prior to being a black belt. He assumed that because Minoru was a white belt, that he was just fighting some weak beginner until Minoru inevitably defeated him with his doumawashi, ending the fight. Afterwards, Takenaka immediately gave Minoru his gratitude for such a great defeat.
After his loss with him, he was so amazed at Kohinata's strength that he looks up to Minoru.
While he was in the high school boxing club, he was known for being involved in an assault case.
After his fight with Minoru, however, he became more focused in karate and after a two year hiatus, Takenaka became a second year in Reinan University and a green belt.
- Takenaka's very first fight in a ring pits him against Imai Yuuto, the semifinalist from the Kaburagi Ryu nationals. Spaced out from fighting in front of an audience for the first time that he doesn't respond to Yuuto's first kick. Total match time, twelve seconds, including the knockout countdown.