Demon Slayer: Kimetsu no Yaiba Tanjiro Kamado, Unwavering Resolve Arc

It is the Taisho Period (circa 1912-1926). Tanjiro Kamado is living a modest but blissful life in the mountains with his family. One day when he returns from selling charcoal in town, he finds the remains of his slaughtered family in pools of blood after a demonic attack. Tanjiro rushes down the snowy mountain with the sole survivor, his sister Nezuko, on his back.