Pan-chan is a baby panda discovered by Mimiko asleep on the doorstep of her bamboo grove home. He instantly bonds with Mimiko, who welcomes him inside. The arrival of Pan-chan's father, Papa Panda, leads to an unconventional family: Mimiko becomes a maternal figure for Pan-chan while Papa Panda acts as a surrogate father to Mimiko. Pan-chan exhibits a playful and curious nature. He frequently tries to follow Mimiko to school despite her instructions to stay home, triggering comedic pursuits by her classmates, driven by his strong attachment to her. He mimics Mimiko, attempting her characteristic handstands with initial lack of success. In the sequel, Pan-chan finds a lost baby tiger, Tora-chan (also called Tiny), hiding in his bed, evoking a Goldilocks scenario. The pair quickly become playmates. Visiting a circus, Pan-chan attempts to copy Tora-chan's ball-balancing act, accidentally causing a disruption that sends circus performers chasing him. This chase results in Pan-chan crashing into the cage of Tora-chan's mother. During severe flooding, Pan-chan helps rescue circus animals stranded on a train. His playful antics with Tora-chan inside a carriage inadvertently set the train moving. The train derails towards the mayor's house, though Papa Panda intervenes to avert disaster. Following this, Pan-chan, Mimiko, and Papa Panda are celebrated as local heroes. Pan-chan's background involves escaping from the zoo with Papa Panda before meeting Mimiko. After their adventures, both pandas return to reside at the zoo but maintain their family life with Mimiko, leaving the zoo after hours to stay with her. His design shares similarities with later Studio Ghibli characters in physical appearance and movement patterns.