Japan, late 18th — early 19th century, the city of Edo (modern Tokyo). Katsushika Ōi is the daughter of artist Katsushika Hokusai. Since childhood, she has shown interest in painting and in the future becomes an artist: she assists her father and creates a number of her own works.
But Ōi's life is not limited to painting. She is destined to meet different people and mystical creatures.
Her childhood friend, Shotaro, dies at an early age and becomes a dragon. Later, he appears before Ōi, and they begin to travel through the mysterious worlds.
In World of Dreams, they meet their common friend, Satsuki, who has fallen into the Red-light district. Together they have to go through a series of amazing adventures...