A perfect prequel for the manga as well as the anime. A very detailed view of the characters and a perfectly fitted side story. If you are a fanatic of Nanba Mutta, you will love this one.

During a random night, the two brothers Mutta Nanba and Hibito witness what seems to be a UFO flying to the moon and they both vow to eventually become astronauts. 19 years later, Mutta has the opportunity to follow his brother and fulfill his promise.—Dielson Sales