Koharu ( Hikari Mitsushima ) lost her husband Shin ( Shun Oguri ) in an unexpected accident. Koharu must go on for her two children Nozomi ( Rio Suzuki ) and Riku ( Rai Takahashi ).

Koharu works hard to make a living, but her financial situation does not improve. She goes to the social welfare office to apply for assistance, but is refused due to not meeting certain requirements.

An employee at the welfare office asks Koharu if she has family that can support her, but she says no. Koharu's father passed away and her mother Sachi ( Yuko Tanaka ) left her and her father for another man ( Kaoru Kobayashi ) twenty years ago. They have been estranged since then.

An employee at the welfare office then contacts Sachi. Her mother makes it known she will provide support for Koharu. Meanwhile, Koharu is stunned by her mother's response. After twenty years, Koharu decides to meet her mother again.

Aoyagi Koharu falls in love with Shin at a railroad station, and before long they are married and have two wonderful children. But an accident suddenly takes Shin's life away and Koharu is left to fend for and raise their children alone. Increasingly poor and with no one to turn too, Koharu is nevertheless determined to protect her children, whatever obstacles come in her way. Even if those obstacles include a frustrating welfare system and even, seemingly, her own mother who she broke ties with 20 years before…