Ninneko or ninbyō (忍猫, literally meaning: Ninja Cat) are able to work with ninja due to their keen senses and unusual flexibility. Many live in Sora-ku with Nekobaa and Tamaki; in Konoha Hiden, ninneko are responsible for providing security to the city's various black marketeers, observing those who visit the city and, if they mean ill, causing them to become lost.
In the anime, ninneko live in a castle and do not possess affiliation with any country or shinobi villages, though a few have been shown to wear a forehead protector with the kanji for truth or sincerity (誠, makoto) written across it. They protect and roam the corridors of the Fortress and intercept any threats.
In Konoha Hiden, ninneko are stated to remove their scent during their standard grooming in order to allow them to move around undetected. Momo displays the ability to use his fleas as projectiles and his food as a clone.
In the anime, ninneko primarily use taijutsu since their flexible muscles grant them great speed. Their claws act as natural weapons, which they can flow chakra into to make them sharper. Nekomata has demonstrated the ability to cast genjutsu.
Bakeneko (化け猫, literally meaning: monster cats) are large cats who have a split tail, giving the appearance of two. They are significantly larger and stronger than the average cat. How the transformation from cat to Bakeneko occurs is unknown.
- In Naruto: Shippūden episode 189, Sakura Haruno observed that a ninneko may be defeated by throwing water over it because cats body temperatures drop rapidly when wet causing them to become lethargic.
- Third Databook, page 129