Минору Тацукава

Кумико's more perceptive younger brother. He is just as devoted to Yamaguchi as Tetsu, since she took them into her clan and trained them even when they were still in school. Along with Tetsu, one of his unhealthy habits is imitating Yamaguchi when Shinohara-sensei visits their dojo. For this, Yankumi usually decides to "train" with them.