The series follows in the footsteps of manga such as Doraemon and Obake no Q-Taro in that the alien Ganmo (who resembles a chicken wearing sneakers) sets out to help his adopted human friend Hanpeita. The series follows the antics of the duo as they find themselves in the middle of much comedic mischief.

One morning Tsukune Tsukuda, out of spite, lets her brother’s pet bird go. But later she has misgivings, and comes home with an egg she has found to give to her brother, Hapeita.

Hanpeita isn't all too pleased with the big, odd-looking egg. However, in the meantime it swells up, breaks its shell, and out comes a strange bird-like creature named Ganmo. It speaks like a human being, and comes to live with the Tsukudas.

Not wanting to be a mere freeloader, Ganmo takes the initiative to run errands, clean the house, etc…yet he blunders at everything he does. Ganmo the tries to clear his reputation, but his efforts only ends causing more and more confusion.

One day a charming girl comes moving in the house next to the Tsukudas. Her pet is a stange mina, named Deja-vu. It is foppish but has a poisonous tongue. And it always teases Ganmo because of its odd-looking.

Thus, the world around Ganmo gets into a mess more and more.