Datte, Kimi ga Warau kara

If only they could step into a time machine and return to those carefree days filled with laughter. When Yui transfers to a quiet rural school, she becomes classmates with Ryo. Beneath her bright demeanor, however, she carries a devastating secret: she has been diagnosed with a terminal illness and has only three months left to live. Alongside this grim reality, Yui harbors a deeply personal wish that she cannot bring herself to share with anyone. Determined to help her, Ryo resolves to grant that unspoken wish, hoping to bring her comfort in the time she has left. Yet, despite their efforts, the inevitable weight of mortality eventually catches up to them both. Following Yui's passing, the harshness of reality crashes down on Ryo, forcing him to confront the profound grief of losing someone so important. This manga tells the poignant story of an eternal promise forged between two young people, exploring how the echoes of shared joy endure even after death.