Punpun Onodera is an ordinary Japanese boy drawn as a simple cartoon bird while everyone around him appears fully human. In elementary school he falls for Aiko Tanaka, a girl newly transferred into his class, and builds his plans for the future around her. At home his parents' marriage is falling apart, and an uncle moves in to look after him. The years that follow carry Punpun from that first crush into a harder adolescence, his inner life running far ahead of anything he says out loud.