Rika and I have been dating since high school. Perhaps because we've been in love for so long, our feelings for each other are no longer the same as before. Recently, Rika has gotten to know a fifth-year man who surpasses me in every aspect, making Rika waver. That man is preparing to travel and invited Rika to go along; she agreed and took this opportunity to confirm our current status. Although Rika didn't say anything, I could still sense that something was happening. One day, while sitting alone in a park near home, I saw Konan passing by. She knew everything and sat down to listen to my thoughts, chatting with me and helping to improve my mood. On the day Rika was going to travel, Konan waited for me outside and offered to replace Rika as my girlfriend for three days! And during those three days, I felt like I was back in the early days of love. I got to know her better and gradually developed feelings for her. I tried to confess my love, but she refused, saying that I was Rika's boyfriend, her sister, and that there would never be a result between me and her...
