The slapstick romantic comedy centers around an ordinary  16-year-old high school boy named Yūto Amakawa who is protected by a  spirit—specifically, a beautiful, sword-wielding cat girl spirit named  Himari. Yūto is descended from a family that has subjugated demons since  time immemorial. The charm that once protected him is now impotent, but  fortunately, at that same moment, Himari appears before him as his new  guardian.