In a troubled time for the Clans, three young cats, grandchildren of the legendary Firestar, begin their training as warriors and, in the course of many adventures, discover their true destiny.

"In Taisho-era Japan, kindhearted Tanjiro Kamado makes a living selling charcoal. But his peaceful life is shattered when a demon slaughters his entire family. His little sister Nezuko is the only survivor, but she has been transformed into a demon herself! Tanjiro sets out on a dangerous journey to find a way to return his sister to normal and destroy the demon who ruined his life...?... he fight with Kokushibo, the highest-ranking demon among Muzan's...

Troubled because her brother has told her that the future of Earth is bleak, a little girl goes to her grandmother who assures her that there are many possible futures and encourages her to use her imagination to explore some of the alternatives.