In this fanfiction, perhaps Naruto is on a mission to find a special power or item that is said to be hidden among the Houndooms. He lives with them to gain their trust and search for it. Along the way, he has to adapt to their lifestyle, like their nocturnal habits and their way of hunting. This experience changes him, making him more in tune with nature and its creatures.
Well, one possible plot could be that Naruto, being his adventurous self, stumbles upon the pack of Houndooms in a hidden forest. He decides to live with them to learn their ways. Maybe he discovers that the Houndooms have a unique form of communication that he tries to master, and this new skill helps him in his future battles or interactions with other ninja.
The plot might involve Naruto living with the Houndooms as a form of exile or self - discovery. He could find that the Houndooms are being hunted by some evil force. So, he takes it upon himself to protect them. In the process, he forms a deep bond with the pack, and they end up becoming his new family of sorts, with each Houndoom having its own distinct personality that Naruto grows to love.