Despite the immediate challenges following becoming a devil hunter with the Public Safety Bureau, Denji has quickly adapted to his new life and responsibilities. As the chaos of Denji's first ordeal with Public Safety settles down, the elite devil hunter Makima decides to take Denji out on a date. Although the date strengthens his affection for Makima and he swears to not fall in love with anyone else, Denji soon finds himself in a tricky situation when he meets a seemingly innocent cafe worker named Reze.

With her forward and flirty demeanor, Reze immediately captures Denji's heart, driving him to frequent the cafe where she works and deepen his relationship with her. However, Denji is completely oblivious to the fact that meeting Reze might have grave consequences beyond simply deciding which woman his heart belongs to.