Erie Daemon is a high school English teacher, enjoying his quiet life. Till one day his class gets attacked by a demon, a mischievous Imp. After saving his class from the Imp- his world seems to no longer be peaceful. Demons keep coming to corrupt the middle realm and The Defense Against Hell’s Supernatural Activity Division threatens Daemon's teaching license and his peaceful life if he doesn't use his skill to find out what type demon Demelza is. However, she seems to be just a normal girl?