Inukami: a mystical being with a doglike appearance that forges a contract with a powerful human tamer to eliminate monsters and demons that prey on the innocent.

In a mansion high above the city, the life of Shindo Kei, the last remaining heiress of the Shindo family, hangs in the balance. Centuries ago, a Grim Reaper placed a curse on the Shindo family: none of its heirs would live beyond their twentieth birthday.

With Kei's final birthday just hours away, Kawahira Keita and his plucky Inukami partner, Yoko, have challenged the Grim Reaper to a duel. If Keita wins, the Shindo curse will be broken forever, Kei's life will be saved, and Keita and Yoko's financial troubles will be a thing of the past. But the Grim Reaper isn't known for playing fair, and has some dirty tricks up his tattered sleeve.

Inukami: a sacred being with a dog-like appearance that forges a contract with a powerful human tamer to help him eliminate evil monsters and demons.

Teenage slacker Keita Kawahira Keita is the descendant of a long line of Inukami-tamers, but seems to lack the necessary ability and has been therfore been forsaken by his family. One day, he meets a cute Inukami named Yoko, who, at first glance, looks graceful, obedient, and beautiful...but after forging a contract with her, Keita discovers that Yoko is a wild and mischievious Inukami that no one has ever been able to control.

Keita and Yoko travel Japan selling their services as demon exterminators, fighting insane threats like panty-stealing ghosts, drunken genies, and obsessed otaku, but mostly fighting each other. While Keita tries desperately to tame Yoko, the rest of the Kawahira clan intervenes, sending a squad of Inukami to whip Yoko into shape, with explosive results!