Nao, a married woman, heard rumors that there were many thieves in her neighborhood who only stole bicycle seats. She told her husband about it, as Nao often rides her bike and was advised to be careful. Nao optimistically thought she was a story without relevance, but in reality, she was being followed by a man with a bicycle seat. One day, while she was trying to go shopping for herself, she discovered that her bicycle seat had been stolen. A man holding the bicycle seat spoke to her when she saw it, and she turned back to find Nao feeling sad.