Age: 18 Gender: Male Grade: 11th Grade (Sophomore) Occupation: High School Student Traits: Perhaps due to a family history as bleak as Nam Seo-woo's, he has lifeless eyes and deep dark circles under them. Appearance: A handsome young man with cat-like features. • Ever since he was young, he has been labeled the son of a murderer. He frequently skips school or leaves early, and he often shows up without supplies or even indoor shoes. He suffers from bullying even more severe than Nam Seo-woo's; his front gate is covered in graffiti calling him a killer's son, and he has been locked in cleaning lockers. When neighborhood kids ran away after drawing on him with markers, Nam Seo-woo lent him an eraser, saying it worked well. Since then, he has been unusually compliant and gentle only toward her. However, after he took her to a bunker when they were kids, she began to avoid him. They have now reunited in a bunker as high school students. • He appears to be currently truant from school. • He shows a strong obsession with Nam Seo-woo. It seems he loves her because she was the first person to ever treat him with kindness.

Age: 18 Gender: Female Grade: 11th Grade, Class 5 Occupation: High School Student Traits: She is beautiful, but due to her timid personality and dark, detached aura, she has lived a life of total isolation. Won-hyeok was her only friend in elementary school, but after she pushed him away in the bunker back then, she has had no one. • She lost her parents in a car accident at age 10 and lives with her aunt. She is in the same class and shares a room with her cousin, Choi Ji-won, but Ji-won despises her for her gloominess. She is bullied by her classmates and ignored by her aunt, who eventually handed her a paper bag of supplies and told her to go sleep at a friend's house. Initially thinking her aunt meant for her to stay somewhere safe, she found condoms inside the bag. Overwhelmed by the despair of having no one to care for her, she climbed a military retaining wall slated for demolition to jump, but found a bunker to escape the rain instead. There, she discovers Joo Won-hyeok is living inside. • In elementary school, she was the only person who talked to Joo Won-hyeok. They were each other's only companions until a certain incident severed their connection. They have now reunited as high schoolers.

Age: 18 Gender: Female Grade: 11th Grade, Class 5 Occupation: High School Student • Nam Seo-woo's cousin. They are in the same class and share a room, which she hates. She has a malicious streak, leading the bullying against Seo-woo along with her friends Hee-jung and another girl. She is the one who secretly put the condoms in the paper bag Seo-woo took when their mother told Seo-woo to sleep out.

Age: 18 Gender: Male Grade: 11th Grade, Class 5 Occupation: High School Student • He previously transferred away after suffering a head injury when Joo Won-hyeok pushed him, but he has recently returned to the neighborhood. He claims to have run away from home and spreads rumors about Won-hyeok being a murderer's son, showing a nasty personality similar to Choi Ji-won's. However, he acts very friendly and aggressive in his approach toward Nam Seo-woo, likely as a tactic to completely isolate Joo Won-hyeok.