Dorobune ni Gobousei

The devil's job is to make a contract with humans and grant their wishes in exchange for energy. If Kuina can't get a contract in the next year, he will be sent to the bottom of hell. The candidate he reluctantly chooses, Inori, is adamant that she has no desire for anything at all... A year-long battle between a desperate devil and a selfless girl begins! (Source: Shueisha, translated)