Kyoko Hori is your average teenage girl... who has a side she wants no one else to ever find about. Then there's her classmate Izumi Miyamura, your average glasses-wearing boy in school and a totally different person outside. When the two meet unexpectedly, they discover each others' secrets and develop an unexpected friendship.

Three years ago a Hero sealed a Hell Gate. The Seal has been weakening ever since, sporadically letting monsters through. After a big group of monsters entered the country through a Hell Gate, Heroes were needed again.

Touka Scott a radish farmer in the southern sown of Cheza is prepared for sudden monster attacks. He built himself a hidden pit-trap with bamboo spikes, to lure unsuspecting monsters if they ever try to attack the village. A monster attacks and Touka fails to lure it into the trap with freshly roasted bacon. Thankfully the local Hero saves the village from the monster in the nick of time. The hungry Hero tries to grab a bite of bacon after vanquishing the monster, only to stumble into Touka's pit-trap and die.

After causing the local Hero's death, Touka is forced to take matters into his own hands to protect the region from attacking monsters.