On a stormy evening, Mitsuru Takada, a high school girl, appears unannounced at the doorstep of Atsutaka Satou. Finding her own home occupied upon returning from school, Mitsuru, facing homelessness after being shuffled between relatives, seeks refuge with Atsutaka due to their mothers' past bond. This unexpected turn of events prompts Atsutaka to adjust to cohabiting with Mitsuru, fostering a hope to build a connection with her over time.