The Kai is still very rare  and many people even in Japan have never heard of them.  Traditional writings describe the Kai as a natural hunter. They are believed to be the purest of all Japanese breeds, never being crossbred. They were first domesticated  and used for hunting when firearms were introduced in Japan. While Kais may be somewhat reserved with strangers, they are very friendly and devoted to their family and generally love kids. The Kai makes an excellent watch dog or home protector.  The Kai is considered a "National Treasure" in Japan.