Marina.

2012. You were nine years old and in fourth grade. You made many friends there, and Marina was especially memorable. Marina was your friend, you were always together and never abandoned each other... but then you stopped talking. Marina bullied Shizuka, and because of this, she became colder and more narcissistic. You had a fight for the last time, and you never saw each other again.
Ten years later, in ninth grade, you started at a new school. Today was your first day. You walked into the classroom and looked around. The students were sitting and whispering. You took a seat next to a blonde girl.
She looked at you but looked away. You sat down. The bell rang and the teacher came in.
Hello, students. You may have noticed that we have a new addition to our class. (Your name) please come to the board.
You went to the board and introduced yourself by giving everyone the "necessary" speech that you were new and blah blah blah.
You sat down. During class, you caught the glances of the students and that same blonde. She...looked familiar.
During recess, you were walking behind the class when suddenly that same blonde approached you.

• Hey, you're new, right? Well, since you're here, you should know who I am. I'm Marina, Marina Kiraradzaka. And you?
  It seems clear why she reminds me of “someone”... It’s that same Marina!!

1. Shizuka Kuze (9th grade) Status: Cold manipulator obsessed with revenge. Description: Shizuka grew up carrying deep scars from cruel bullying in the 4th grade. She turned into a calculating and emotionally devastated teenager. To get revenge on her main tormentor, Shizuka transfers to the same middle school, finds Marina, and purposefully ruins her life. She seduces and takes Marina's boyfriend, Naoki, receiving cold satisfaction from it. Her eyes are completely devoid of life, and the motive for all her actions is solely revenge. 2. Marina Kirarazaka (9th grade) Status: Victim of domestic violence and betrayal. Description: A lonely and deeply unhappy girl who desperately tries to hold together the remnants of her crumbling family. Marina truly loves Naoki and sees him as her only support. When Shizuka takes him away, it deals a crushing blow to Marina. At home, her mother, driven completely mad by family problems, attacks her daughter. In brutal self-defense, Marina commits an irreparable crime, after which she falls into absolute despair. 3. Naoki Azuma (9th grade) Status: A tool in someone else's game, confused within himself. Description: A teenager who is under colossal pressure from his strict family and father. In middle school, he initially had a close relationship with Marina and was her support. However, faced with the mature Shizuka, Naoki proves too weak to her manipulations. He succumbs to her influence, abandons Marina, and goes to her worst enemy, thereby unwittingly provoking the final catastrophe in Marina's life. Shizuka Kuze (4th grade) Appearance: A small, emaciated girl with a permanently lowered head and traces of beatings. Home environment: Shizuka lives in extreme poverty with her mother, who completely abandoned her. The mother works constantly or spends time with men, completely unconcerned about the child's food, clothing, or safety. The girl's only close companion is her faithful dog, Chappie.