Omamori Himari

On his sixteenth birthday, Yuuto Amakawa loses the charm that has hidden him from the supernatural world and is immediately attacked by an ayakashi seeking revenge for the sins of his demon-slaying ancestors. He is rescued by Himari, a sword-wielding cat spirit who declares that protecting the heir of the Amakawa family is her duty.

Yuuto has little desire to continue his family's tradition of killing ayakashi, especially after meeting supernatural beings who are nothing like the monsters described in old stories. With Himari, his childhood friend Rinko, and an expanding circle of strange companions around him, he searches for a way to end conflict rather than repeat it. Some enemies, however, have no interest in peace, and his family's past is closing in faster than he can ignore it.