Masaaki Nakatani coaches Shūtoku High School. He and Kagetora have history—they go way back and apparently ran into each other at the Winter Cup, where it came out that they'd known each other for years. The two are pretty familiar with each other, calling each other by nicknames like Tora and Ma-Boy, which hints at whatever their past together was.
Content compiled by AnimeList.moe from publicly available sources.
