Humanity has abandoned Earth after an environmental disaster. The survivors travel in a gigantic spaceship looking for another planet similar to earth. They find what appears to be an attractive planet: Monstria.
The only problem is it’s full of MONSTERS! Fearful of the monsters humans are kept on board until eleven-year-old Alfa discovers that a monster has made its way aboard. Alfa finds out the little monster, Nefu, is in fact friendly and decides to help it go back home. With a series of events Alfa, Nefu and humans discover the truth about Monstria and all of its residents.