Sachi Kawakami and Takara Tsukishima are an ordinary high school couple navigating the everyday joys and challenges of young love. They attend the same school, spend time together, and have begun exploring the more intimate side of their relationship. However, their seemingly normal life is upended when Sachi begins to feel that something is physically off. Seeking answers, she secretly buys a pregnancy test and, alone in a family restaurant bathroom far from her neighborhood, stares in shock at the two red lines that confirm she is pregnant.

The series follows Sachi and Takara as they grapple with this life-changing revelation, forcing them to confront difficult questions about their future far earlier than they ever imagined. The story explores the emotional and practical realities of an unexpected teenage pregnancy, not as a cautionary tale, but as a humanizing portrait of two young people facing an overwhelming situation. As they wrestle with their options and the decision of whether to become parents, they must also navigate the reactions of their families and friends. The cast includes Sachi’s mother Harumi Kawakami, her father Kei Kawakami, and her brother Ko, as well as Takara’s mother Naomi Tsukishima, alongside their friends and classmates including Nozomi Yazawa, Hayato Sasabe, and Yuto Okita, all of whom are affected by the couple’s circumstances in different ways. The narrative arc focuses on how this crisis tests their relationship, their maturity, and their place in a world that may not be ready for them to become parents.