The "Nyanbo" are extraterrestrial beings with square bodies, ears, and tails that arrived on Earth from outer space. Among them is Tora, who dreams of fixing their damaged UFO and returning to space, along with his sister Kotora, the precocious Shiro, the mischievous Mike, the mysterious Kuro, and many others. These Nyanbos now live happily in hidden locations, behaving much like cats—free-spirited and occasionally getting into trouble.