Onbaa

Onbaa is an bear/monkey-like animal who Jiraiya had encountered during his journey as a child, then wrote a story about it. Tsunade thought it was a lie until she saw the creature. A newborn Onbu is abducted by a hawk that Naruto scares, causing it to drop the newborn Onbu on Naruto's back. Having mistaken Naruto for his mother, it clings to his back and cannot be removed. Naruto is forced to leave the village for a mission to attack some bandits that Tsunade ordered him to attack. On the way back to the village Naruto is attacked by Onbu's enraged mother who mistakes Naruto for Onbu's kidnapper.

When separated from Naruto's back, Onbu matures into a violent adult that attempts to kill Naruto. After being reminded of Naruto, Onbu blocks his mother's deathblow to Naruto. Onbu, himself, carries an unconscious Naruto back to the village. Before traveling out of sight, Naruto wishes Onbu luck with his mother. Soon after Onbu leaves the village, the entire population of Konohagakure is mistaken as the mothers of countless infant Onbaas as Tsunade begs Naruto to tell her how he removed Onbu from his back. Naruto joked that she should have a sumo match with it like Jiraiya did, thus angering her even further.