Incest Tokyo mother

The night before her son Masao got a job and left for Tokyo, Shino sat around the last meal with her husband and younger brother Takashi. Masao was feeling uneasy about Tokyo, a big city he had never seen before, but he felt the warmth of his family and went to bed slowly that night... A few days have passed since he started living in Tokyo, and Masao is nostalgic for his hometown and family. One day, Masao's mother Shino suddenly visits him. While Masao is unable to hide his surprise at his sudden visit, Shino discovers an unfinished letter and learns about Masao's feelings.