A weary middle-aged man is approached on the street by a pure and adorable student named Aoi Nakajo. Noticing his dejected appearance, she sympathetically says, "My dad left when I was young, but the father I remember was so energetic and kind. When I see sad-looking dads like you, it gives me strength," and hands him a canned coffee she bought with her meager allowance. Touched by her kindness, the man grows increasingly drawn to her each time they meet. Eventually, Aoi reveals she's from a single-parent household and struggling financially, stirring deep emotions within him. Falling for her, he offers financial support, which she gratefully accepts, tearfully saying, "I hope I can marry someone like you someday." Satisfied, he continues helping her—until one day, after giving her money, he chases after her to return a forgotten item and witnesses her on a date with another man. Overhearing her laugh, "I'm just letting them dream while I take their money—can't say I'm not getting away with something good," the man is shocked by her true nature. Filled with rage, he resolves to take revenge on the deceitful, promiscuous Aoi and deliver his own punishment.