Su-ho is quite the handsome guy, at the time he was seen as a model student and was very well-known for his grades and attractiveness. He has short auburn hair with bangs that cover his forehead. His eye color appears to be orange, leaning towards brown at certain parts. Su-ho is a kindhearted individual who likes to help others in order to make them happy, which he claims makes him happy. He only enters academic competitions if there is prize money, which he uses to donate as financial support for his class, such as to pay off students' lunch fees. He goes out of his way to fill out all the forms for a district supported business application that only needs a teacher's signature to sign off on it. He is sometimes immensely naive at times and sees school as nothing but a playground and prefers to not put much effort into his studies. However, when he actually puts his mind to it, he can easily score high, even surpassing Yeon Si-eun in the academic rankings and even scoring perfect scores across all subjects. He is protective of Si-eun and doesn't want him to become a target, nor does he want him to worry. No matter how many times Si-eun asked, Stephen wouldn’t tell him about anything that was happening to him. When Si-eun reveals to him that the class has been insulting them behind his back, Su-ho regrets getting Si-eun roped into the mess. He thinks he might break if Si-eun ends up getting hurt too and tries to assuage his worries by claiming he's good at taking hits and not to worry about it. As an act of defiance against the bullies and to ensure their focus is all on him instead of Si-eun, Su-ho disobeys Oswald's orders to score a zero on the monthly exam and instead scores first place in the entire school with a perfect score across all subjects. Su-ho liked to help others and bring joy to their lives, to the extent that some questioned whether his intentions were genuine. He sleeps through a lot of classes and is seen as lazy or unmotivated to others who do not know him. Su-ho works multiple jobs after cram school to support his grandma.

Freakishly cute little guy. Quite timid of people but unafraid of helping others in need. Extremely shy, but once befriended, he won't leave your side.

One of Su-ho's friends. Hot-headed and short-tempered, known to power through his fights on pure guts and grit alone. He has mellowed out somewhat after middle school and ignores the trash talk that once enraged him. He is also rather impulsive and quick to start a fight. Despite his temper, he is very caring towards his friends, especially exhibited when he expressed concern for Si-eun when he was hospitalized. Despite his reputation for being in fights, outside of fighting, he is a very chill, outgoing and socially supportive and welcoming person who is an extremely extroverted and loves making friends.

Also Su-ho's friend. Park Hu-Min, also known as Baku, is above-average height, with a rather muscular frame. He has reddish-brown hair, which initially goes down to his chin but is later cut to reach his ears. Ben has a notably darker skin tone than most of the other characters in the series. Baku usually wears the Eunjang High uniform, although he usually leaves his shirt unbuttoned and neglects the tie, giving him a somewhat casual, unkempt appearance. Baku has a scar on his left upper forearm as a result of shielding Su-ho from the pile of wooden beams with nails. In its first appearance, it went down his arm vertically and had what appeared to be pins or staples. In its next appearance, the design of the scar has changed to a typical horizontal scar partially wrapped around his bicep. Baku is the friendliest of all the boys in the friend group. He shows protective and possessive traits to his friends and treats everybody as an equal. He is one of the strongest of Eunjang, people even going as far as calling him the designated "protector" of the school. People often feel very safe with him. He is trusted and severely dislikes bullies.