By night, junior high student Yoshimori Sumimura is a kekkaishi - a demon-hunter who specializes in creating magical barriers around his prey. By day, Yoshimori's got some other demons to battle: an addiction to sweets and a seriously crotchety grandfather! Yoshimori's pretty 16-year-old neighbour and childhood friend, Tokine Yukimura, is also a kekkaishi, but their families are feuding over who is the true practitioner of the art.

When he's unable to capture a particularly nasty foe, Yoshimori vows to improve himself, even if it means spending less time baking cakes! Then a spectre from the past visits Madarao, Yoshimori's loyal demon dog, and attempts to lure the canine away from Yoshimori forever.