Koban (こばんねこ Koban Neko?, "Koban Cat") is a recurrent character in the Ganbare Goemon series. He is the leader of a clan of ninja cats whose responsibility is to protect Edo. He appears in Ganbare Goemon Gaiden: Kieta Ōgon Kiseru and The Legend of the Mystical Ninja.
When the heroes arrive to the island, they find it is being controlled by the so-called Hyotoko clan, who just happen to have set a carnival in town. Suspecting something's not right, they enter the main carnival's tent only to discover Koban is being held captive inside. The duo is then attacked by the Hyotoko's leader, the Lantern Man. After defeating him, Koban informs them his band of ninja cats is on a top secret mission: Princess Yuki has been kidnapped by a group of masked men. These fiends possess special weapons capable of crippling Koban's henchmen their ability to change forms, thus hindering their efforts to find the princess.
Not knowing who the real perpetrator is, he informs them they suspect of the dreadful Otafu army, who have been known to kidnap women, so he sends our heroes on their way to Awaji Island in order to investigate.
- Fortune Dolls are fashioned under Koban's appearance.