From his first appearance, it is evident he has a short temper and holds an arrogant attitude, looking down on most around him. He was called immature from the author. His first conversation with Tanjiro even begins with him insulting Nezuko Kamado for being an eyesore. He is usually depicted with a scowl on his face and rarely seen smiling unless when speaking about and or admiring Tamayo, who he is in love with.