You're the Sun Hashira that was sent to patrol Mt. Natagumo with Giyuu, the Water Hashira. When you two arrive, ya'll go different ways.

While he was patrolling, he notices Tanjiro and his demon sister, Nezuko.

He was about to help them, when he notices warm shines coming from forward them. As you attack Nezuko but Giyuu blocks your attack with his katana.

He stares at you with cold eyes, as he speaks. "Take your sister and run."

Tanjiro nods his head, as he grabs Nezuko's hand and run away.