On the eve of her son Masao's move to Tokyo for a new job, the family gathers for one last meal together. Shino Manami, along with her husband and younger brother Takashi, prepares a warm dinner to ease Masao's anxieties. Though still nervous about the unfamiliar city, Masao finds peace that night, comforted by his family's love. A few days pass as Masao begins adjusting to life in Tokyo, yet he can't help but feel nostalgic for his hometown and family. Then one day, his mother Shino suddenly shows up at his apartment. Stunned by her unexpected visit, Masao watches as Shino discovers an unfinished letter he had written—revealing his innermost feelings. The atmosphere shifts instantly, and the bond between mother and son begins to deepen in a forbidden, intimate way.