Before becoming a Demon Slayer, Tanjiro’s family was slaughtered by the Demon Lord Kibutsuji Muzan, and although his younger sister survived, she was turned into a demon.

Nezuko is the eldest daughter of the Kamado family. She grew up on a mountain with her older brother Tanjiro, her younger siblings, and her mother. In the family, Nezuko helped her mother take care of the younger children after their father passed away.

Inosuke was raised by wild boars before taking part in the Final Selection. Later, the series revealed that he had lived in a family with a violent and abusive father.

Zenitsu was an orphan, so he did not receive a proper education. Before learning the Breath of Thunder, Zenitsu had once fallen in love with a girl.