When Satoshi was little, his mother Akiko always took good care of him. She was gentle, but mentally strong. However, two years ago she was diagnosed with cancer and now it's Satoshi's turn to comfort and care for her. However, despite his best efforts, she passes away. A year after Akiko's passing, Satoshi, his father Toshiaki and his older brother Yuichi start new lives. Around that time, Satoshi receives a present from his mother.