Osomatsu-kun Season 1

Osomatsu and Choromatsu mind Chibita as babysitters, but grow bored and decide to have a mysterious dog take the heed instead. Meanwhile, Dekapan creates a robot powered by spare change that inadvertently leads to disaster in the hands of the sextuplets.

Iyami attempts to con Osomatsu, Choromatsu, and Chibita out of their hard-earned money at his fishing pond with a rare fish that gives them all their money back if caught. Later, Chibita plays the role of the leader of a gang of thieves who targets Osomatsu for discovering their misdeeds.

Totoko's grandpa enlists the help of the sextuplets to stop Chibita and his gang of feral cats from attacking the fish store. Later, Iyami and Chibita fly around town in a helicopter to cause mischief amongst the locals.

A housework robot (shaped like Chibita) causes havoc amongst the Matsuno family when he malfunctions. Meanwhile, Iyami runs a scam out of a laundromat to catastrophic failure.

Iyami and Chibita feign construction workers to scam the sextuplets out the their money by making a paid shortcut to school. Later, a camera company offers a cash prize for whoever can photograph a face-making man without any made faces, leading the sextuplets and Chibita to try to claim the reward.

Spooky things seem to be happening around town, leading the sextuplets to discover a secret of their own appearance. Meanwhile, Chibita challenges the brothers to a martial arts battle.

Iyami scams the sextuplets with a magic kettle, actually utilizing Chibita as the secret inside. Later, Chibita and Bokeo get revenge on the sextuplets for harming their frog friend.

Chibita appears alongside Totoko wearing a strange hat that when removed, changes his temperament from good to bad, leading to chaos amongst the Matsunos. Meanwhile, Chibita goes boar hunting and encounters the sextuplets and Iyami.

Osomatsu visits dentist Iyami's office for a toothache, but due to an unpaid bill, assists him in fixing up the mouth of Dekapan's crocodilian "son". Later, after Chibita's mosquito colony is destroyed by the sextuplets, he and Iyami create a watermelon-shaped bomb to enact revenge.

Chibita, with the help of his scientist uncle, devise a plan to shrink the sextuplets down to flea size so that he will no longer be shorter than them. Meanwhile, a roaming minstrel and Chibita team up to enact revenge on the sextuplets with their army of cats.