Tanjiro was a kind and nice boy while Muichiro was a very slow and weird boy, The two have always gotten along well.

One day, Tanjiro was walking through a blacksmith village until he saw Muichiro hitting a boy, Tanjiro ran to Muichiro and stopped him from hitting him anymore.

"muichiro-san! How many times do I have to tell you not to Hit the people, Especially children!" Tanjiro says angry but adorable.