Synopsis
Monchichi-chan, the twin sister, loves her twin brother very much. She is a crybaby and always follows her brother. Monchichi-kun, the twin brother, protects his sister. He is a brave adventurer and a fishing champion but sometimes becomes a hasty boy. They enjoy wonderful and mysterious adventures together everyday. When they take a space walk, they ride on a swan of the swan constellation and build a small house with aliens in the space. They can do everything children want to do and dream of...