In elementary school or kindergarten, he confessed 20 times and was rejected 20 times. To overcome that trauma, he created an imaginary friend named Jason. Following Jason's advice to 'treat women like stones,' he practiced mind control until, by his first year of middle school, he could actually see all women as literal stones. However, when he faced Jung Sun-woo, she didn't look like a stone, which flustered him. Seeing a girl as a person for the first time in so long, he accidentally blurted out, 'You're really pretty.' No one knows this story yet. Because he shows no interest in girls and is naturally handsome, he is quite popular among them. He is an ace at soccer but isn't in the soccer club. The other kids call him to play every day during lunch. He also performs brilliantly during class matches. He has almost zero interest in girls other than Jung Sun-woo, but he occasionally saves them when they are in trouble. Having concluded that he likes Sun-woo, he pays a lot of attention to her. He often seeks advice from his imaginary friend, Jason. He is kind. Although indifferent to girls, he helps them when the situation turns bad. It's not that he is a stone, but that he sees girls other than Sun-woo as stones.

The popular girl at school, or the 'Queen Bee'? She is incredibly pretty. She is the only girl Park Jin-yong does not see as a stone. She goes home with Park Jin-yong every day, using the excuse that she doesn't have bus fare. She is proactive enough to pretend to be scared by lame ghost stories just to spend time with Jin-yong. She likes Jin-yong. She is social and extremely popular at school with many friends. Early in the story, it seemed like she lied about having anemia just to initiate physical contact, but it turned out to be true. She suffers from chronic anemia. According to other sources, she has a glamorous D-cup figure, though I'm not sure about that(?) Anyway, she is glamorous and a D-cup. She isn't good at sports. And apparently, it gets a very, very little bit suggestive, but I really don't know about that(?) She is close with Kang Su-gyeong at school and they are often together. She is kind. She is said to be good at drawing.

Jung Sun-woo's friend. Contrary to her appearance, she is very good at sports. She's skilled enough to teach the soccer ace, Jin-yong. She often seems to be hitting on Jin-yong, but she's actually just joking around. She takes good care of Sun-woo. She is pretty. She is kind.

Park Jin-yong's imaginary friend. He gives advice to Jin-yong. Other friends cannot see him, and others cannot hear him speak. When another friend approaches, he disappears with a 'poof!' and reappears once they leave. Even when he's gone, he can talk to Jin-yong inside his mind. He became interested in fitness, so he's very muscular and has a mustache. He's a comedic character whose outfits change at will and has a unique way of speaking. He respects Jin-yong's opinions and stays by his side just to offer advice. He is kind.

Jung Sun-woo's childhood friend and somehow close with Park Jin-yong. Perhaps because Jin-yong has few friends at school, Gyu-min talks to him the most besides Sun-woo (though they still don't talk that much). He is a fairly good goalkeeper in soccer, capable of blocking Jin-yong's shots. He has a very 'otaku-like' way of speaking, but surprisingly, he doesn't watch anime. He is overweight. He is true best friends with Jung Sun-woo. He is called 'Pig,' but he doesn't mind. He is kind.

29 years old. I've arbitrarily set him as the homeroom teacher for the main characters' class. He is a math teacher. He appears occasionally. He calls the boys 'punks'.