©2018 STUDIO CHIZU
A small house with a small tree in a small yard in the corner of a city somewhere.
Kun, a spoiled little boy, has a new baby sister. Ever since her arrival, he misses his parents' affection and is baffled by things he has never experienced before. Then one day in the yard, he encounters a mysterious girl called Mirai who calls him "brother."
Guided by Mirai, Kun travels through time into stories about his family. It is the beginning of the little big brother's big adventure.
Magical worlds that await him. A mystery man who claims he was once a prince. A fantastical experience with his mother as a child. An encounter with a young man who bears a resemblance to his father.
And his discovery of "family love."
Through his adventures, Kun learns life lessons that help him grow in baby steps. Where does he finally end up? And what is the real reason for Mirai's visit?