It's a beautiful summer day Len is playing with Mikuo in the sand. Rin is looking at Mikuo and Len with a solemn look on her face Len asks Rin to join him but she just goes back inside the beach house. Miku tells Kaito to go check up on Rin because she's been acting withdrawn from the family. Kaito looks at Len he's happy he has a little brother he could play with. Len has been getting worried about Rin because he wants to be with her but he has big brother responsibilities such as watching over Mikuo. He wants to spend some twin bonding with Rin but he can't he has homework and he has to babysit Mikuo.
Around 5 p.m. The family has a barbecue and Kaito fires up the grill and makes food. He looks at Rin and has Meito man with the grill while Luka is trying to make sense of the instructions on how to clean it. Sakine is talking to Len and is laughing because of his funny joke about the banana and the monkey. Kaito is trying to talk to Rin but she doesn't want to deal with anyone at the time she was 14. She hit puberty when she was 13 so her hormones were messed up and it was a part of growing up. Len is starting to notice how Rin is really withdrawn and is at the edge of her string he wants to bond with her again but she couldn't because puberty changed her judgment. She was more depressed not the cheerful Rin he knew. Len was walking toward Rin asking for some bonding time so they went to the porch on the front to talk to Rin and have some bonding time. Len has small talk with his twin he tries to hug her but she doesn't want to be hugged so she pushed him to the ground and walks away.
"Rin what's wrong? What happened to you?" Len asks getting up.
"Leave me alone Len you wouldn't understand!" Rin says agitated.
"Please why are you doing this to me?" Len asks.
"Just leave me alone next time you bother me again you won't see light again." Rin says agitated.
Rin walked away, she hated herself she is starting to act more like Meiko. It wasn't her fault, she felt that she couldn't trust anyone anymore. She felt hopeless but Kaito had more than just his twins but he has Mikuo. Kaiko asked Miku about Rin because she doesn't seem like himself. Kaito notices that Len is starting to hit puberty because he could hear his voice crack at time. Mikuo would laugh at Len because he would say that he sounds like Miku. Rin wouldn't laugh at that joke she just ate and left without saying a word. Len wants to help her but she refuses. He's going through changes as well but it's not going to stop him from trying to find out what's wrong with her.
The next morning was normal it's around 10 a.m. Len and Kaito are up and they go downstairs to make some breakfast. Miku gets up and walks downstairs where she greets Len and Kaito. Breakfast was almost done and Kaito decides to wake up Rin. He walks in and her door wasn't locked he opened it up and finds that Rin wasn't there. He quickly checks the other room and he notices that she wasn't there or anywhere in the beach house. Kaito tells Miku and Len what happened. Rin ran away from home and will most likely never come back. They decided to eat their breakfast and Mikuo asked Len what happened and he tells him that Rin ran away. He no longer has an older sister. Len hated himself if only he reached out to Rin she wouldn't have ran away. He no longer has anyone that is part of his immediate family; Rin was all he had left.
Kaito called the cops and reported that Rin ran away from home. He is asked questions and was told that he would have to call back after 24 hours because she could come back. Rin would never come back anymore. After the 24 hour waiting period he called again and reported Rin as missing. Len had trouble sleeping the next few weeks he missed his twin and was often crying in his sleep. He wished he knew this sooner and he felt like he could no longer live without Rin who was his only connection to his biological mother. For the next few weeks Len put missing posters of Rin because he knew she was still alive. He missed her and he had to stay strong for Mikuo he sees a figure wearing an orange hoodie and he/she walks away and starts running away from him. Len has been asking Kaito if there was any news if Rin was found. Kaito told him that nothing came up; Kaito is already stressed out as it is after Rin decided to run away. Len started having trouble focussing in school since he's worried about Rin. Whenever he was bullied Rin would do nothing only help them beat him up.
He spent a year of school without Rin. His sophomore year was tough because he didn't have his twin around even though she was hostile at times he still loved her as a sister. Len wanted to talk to Miku about it and she tells him that she'll come back eventually. During his breaks he would play video games with Oliver. Oliver found out and he missed her too he wanted to ask her out. Kaito tried his best to find out any information of Rin's whereabouts. Life will be hard until a fateful day occurs.