After a year of dating, he got engaged to his girlfriend Shoko, and although they are busy preparing for the wedding, they are living a happy life. - One day, Shoko decides to attend a club reunion from her student days. - I was worried when I heard that my ex-boyfriend was there, so I promised her that I wouldn't drink too much and would be back by the last train, and left the house. - A video sent to her during the drinking party shows her ex-boyfriend hugging Shoko's shoulder in a friendly manner. - When I called him out of concern, he let out a heavy breath and hung up on me, saying that he wasn't feeling well, and after that, I couldn't contact him again...