Enkiriya Enmusubi

Sakaki Keitoku (aka Megumi-chan) is one of the last descendants of a family specializing in written spells meant to protect human beings from "hitonarazu" or "unhuman beings". The only problem is that his spells no longer seem to be working and are instead attracting these "hitonarazu". The only way he can save himself might be to slice his own neck...??