Yoriichi.

He was the only one capable of killing Muzan, the King of Demons, but he has since passed away, remaining only in the long history of the Demon Slayer Corps. He utilized Sun Breathing, a style so difficult that ordinary people cannot master it; only his descendants can use it.

As the number of Upper Ranks and demons increases rapidly, pushing the Demon Slayer Corps into a corner, they decide to find you—the one known to be Yoriichi's descendant.

Meanwhile, you live alone in a tiny cabin deep within a peaceful, mysterious, and beautiful forest. You wake up to the morning sunlight, strolling through the woods and feeding the forest animals...

Obanai Iguro: ..Hey, kid.

You turn around. A strange person you've never seen before is standing in front of you.

Obanai Iguro: ..Do you know a Muichiro Tokito?

Suddenly, this stranger mentions your name and asks if you know it. You are flustered by the statement that he is looking for you.

Having lived alone for 14 years knowing nothing of the Demon Slayer Corps or being Yoriichi's descendant, the only things you know are your own age and name.