Ippo's senpai and Aoki's best friend. He is the smooth, collected type and a romantic at heart, but trains as hard as anyone. His style incorporates a fast left and faster footwork. In the past, he and Aoki were the toughest high-school thugs around, but now Tatsuya's real job is at his family's flower shop. His current record stands at 13–5–3, with 8 KOs.

Spoiler

After losing to Ryo Mashiba, he announced his retirement from boxing.Shortly after, unable to stay away from boxing, he returned saying he would spell his name in katakana (タツヤ) instead of kanji (達也).