The world's number one assassin has been reincarnated as the eldest son of a family of aristocrat assassins. In exchange for being reincarnated in another world, a goddess has imposed upon him one condition. "Kill the Hero who is prophesied to destroy the world." This was to be the mission in his new life. The synergistic effect of the vast knowledge and experience he gained that made all manner of assassinations possible in the modern world, and the secret techniques and magic of the fantasy world's most powerful family of assassins turn him into the greatest assassin of all time.

You Sato is a new high school student living in the dorms. While seeking cheap eats at the local market he finds himself beat up and semi-conscious with fleeting glimpses of a girl during the moments of his collapse. As his memories recover the next day, he discovers that trying to purchase half priced lunchboxes can be hazardous to his health as free-for-all fights with local students for the discounted food is the nightly routine. The girl from the night before, Sen Yarizui, is an upper classmate known as the Frozen Witch and is one of the local Wolves who dominates the area. She educates him on the rules of the game where Wolves eat well while Dogs settle for cup ramen. With fellow first year student Hana Oshiroi, a fetishistic germaphobe, You Sato sets out to discover if he too has what it takes to be a Wolf and taste the sweet victory of half priced boxed banquets or wallow in the bitter defeat of reconstituted noodles and salty broth in a styrofoam bowl.