It is the cat-shaped fortress of Nekomata which is guarded by numerous ninja cats. The ninja cats have shown to not take kindly to humans, as Team 7, who were on a mission to retrieve Nekomata's paw print, had to "disguise" themselves as cats to infiltrate the fortress. It is shown that it isn't completely a fortress as there were restaurants and bars seen within it and that were civilian cats as well. One of the ninja cat guards that Sasuke Uchiha questioned had a headband with the kanji for truth or sincerity (шка, makoto) written across it, like all the hidden villages have. In this RP it's possible to find directions to the Cat Summons Legendary home here.