Hanamoto Shuuji is a professor at the college that the bunch attend. He admits that he's not that good in drawing or painting but he is very effective in teaching the concepts and basics of art. That's why he decided to become a professor. Shuuji is also Hagu's uncle. Hagu looks up to him as his father figure. In return, Shuuji serves as a half- father and treats Hagu as his half- daughter.
He's very protective of Hagu and acts hysterical or heats up whenever someone makes a move on her.
His close friends are Rika Harada and her late husband. He is the person who recommended Mayama to Harada Rika. When Rika's husband died, Shuuji made sure that she won't do anything irrational to herself. Shuuji and Rika are just friends, however, Mayama sees a different point of view.