Puu-chan is an extraterrestrial octopus distinguished by a propeller affixed to his head. Originating from space, he crash-lands on Hoeru Island, inadvertently flattening the local frog teacher Kaeru-sensei during his chaotic arrival. This disruption initially alarms the islanders, but Puu-chan miraculously restores Kaeru-sensei to his original form, gradually earning the wary residents' acceptance.

He forges close friendships with several island inhabitants: a human girl named Mirin-chan, a dog called Porori-kun, and the resurrected Kaeru-sensei. His daily existence revolves around navigating challenges and embarking on misadventures alongside these companions. The propeller grants him flight, aiding exploration and quick escapes from predicaments. An innate curiosity drives his interactions with unfamiliar situations, frequently precipitating unforeseen results.