Office worker Natsuki Souta was cheated on by his fiancée and left with 3 million yen in wedding savings and nowhere to put it. One drunken night, he meets Kanzaki Airi, a high school girl whose mother skipped town and left her with a mountain of debt. On impulse, Souta uses his savings to free her from the thugs collecting it, and Airi moves into his home.

As he showers this girl, who has never known love, with affection, Airi grows attached to him and secretly begins to fall for him. Souta, too, finds happiness in the peaceful days he spends with kind, wonderful-cook Airi.

Then one day, as he’s troubled by his mother pressuring him to “hurry up and introduce your fiancée,” Airi shyly says:

“Um… could I be your fiancée, just for one day, Souta-kun…?”