The story begins on a rainy night, when a homeless little black cat is brought home by a young girl Luo Xiaobai. She names the cat Luo Xiao Hei. However, Luo Xiao Hei is no ordinary cat: he is a supernatural entity that hosts several small creatures called Heixiu. As Luo Xiao Hei new life soon threatened by the mysterious Diting, who commands three winged wolves.

Nearly twenty years into the 21st century, people have forgotten the existence of youkai. When a number of unexplainable phenomena plague adults of the human world with confusion and chaos, thirteen-year-old Mana writes a letter to the Youkai Post in search of answers, only to be greeted by Gegege no Kitarou...

Zundamaru is back... For now! Even without missions, we elite ninjas face grave dangers every day!

Based on the Ninja Awate-maru comedy manga by Jirou Tsunoda.