Naoto Watari is devoted to caring for his younger sister Suzushiro after their parents’ death, earning him a reputation as a “siscon” in his new school. His carefully balanced life is disrupted when Satsuki, a childhood friend with a tense past, transfers in and reconnects with him. As old memories and secrets resurface, Naoto’s world begins to unravel, and he must confront emotional truths he’s long ignored. Caught between protecting his sister and facing personal challenges, Naoto’s quiet life teeters on the brink of collapse. This 26-episode series blends romantic tension, drama, and suspense in a coming-of-age story airing from July 5, 2025.