As Rin experiences the ups and downs of being a teenager, she begins to ponder what it means to be family. In her exploration of that question, she takes it upon herself to track down Masako, her birth mother. Masako, engaged and pregnant, is about to start a new family of her own. But with Masako's feelings of guilt about her treatment of Rin, she can't bring herself to tell Daikichi the new developments in her life. So when Rin and Masako end up meeting fact-to-face as a result of Rin's investigatory legwork, will the mother-daughter relationship that's been all but non-existent till now end in fireworks?