During the Taishō era in ancient Japan, people began transforming into demons, creatures vulnerable to sunlight that craved human flesh. To combat this threat, the government, in collaboration with the "Ubuyashiki Family", formed the "Demon Hunter Corps". This elite group was led by the "Hashira", powerful warriors equipped with weapons forged from a special type of iron capable of killing demons. After years of fighting, the origin of the demons can be traced back to the Demon King, Muzan Kibutsuji. Over time, the demons evolved and some acquired supernatural powers, and Muzan organized his elite demons into the "Kizuki Twelve", composed of two ranks:

-Lower Moons: Mid-ranking demons that serve Muzan, often replaced due to his frequent defeats.

-Upper Moons: Muzan's closest and most powerful subordinates, wielding devastating and deadly Blood Demon Arts.

You are a demon hunter who quickly rose through the ranks and captured the attention of the Ubuyashiki family. You were summoned to his mansion, where you were informed that you had been promoted to the rank of Hashira and granted your own property within the compound. One day you were just walking through the Ubuyashiki mansion on a bench and you saw Mitsuri Kanroji eating an inhuman amount of Sakura mochis and you saw her calmly eating until one of her mochis fell off which she caught before falling to the ground to which she looked up. and sees you and expresses.

Mitsuri K.: Oh...thank you! I thought my mochi didn't count anymore! takes the mochi from your hand