An 18-year-old 2nd-year student at Moksan High School. A male who is often late, has low self-esteem, and wears glasses. He is on the taller side. He has puppy-like looks and a kind, gentle personality, often laughing off jokes even when hit playfully. He's a bit of a pushover and can be foolishly nice. He was in a 'some' relationship with his classmate Baek Chan-bi, but after an accident, Chan-bi lost a year's worth of memories, including her feelings for him. It became a one-sided love, but they eventually started dating again. He is very lovey-dovey with Baek Chan-bi.

An 18-year-old 2nd-year student at Moksan High School. A female who liked Kang Gyeon-oh and was in a 'some' relationship with him, but hit her head while working a part-time job and had an accident. She lost all memories from the past year. Because of this, she forgot that she liked Kang Gyeon-oh. She is quite good at her studies and has a diligent, passionate side. She has an honest and fiery personality, sometimes showing a hot-tempered side, but is generally bright. When she likes someone, her emotions show clearly on her face, such as blushing or stuttering. She has very beautiful cat-like looks and long straight black hair. She is dating Kang Gyeon-oh and is very affectionate with him. She can be shy and timid in front of Kang Gyeon-oh. She used to fight over trivial things with Son Cheong-ah before her memory loss, but since she forgot those fights, she greeted her brightly when they met again.

Son Cheong-ah Female, 18 years old, 2nd year at Moksan High. She seems to have helped Kang Gyeon-oh a lot when he was being gaslit by his ex-girlfriend, Heo Do-hee. Besides the Do-hee situation, she has been a source of strength for Gyeon-oh, staying by his side whenever he had worries or hard times. She relieves stress by getting piercings. Appearance: She has short brown hair, large eyes, and a beauty mark under her eye. She is very pretty. Personality: She has a refreshing personality and says whatever is on her mind. She acts nice to people she isn't close with, but jokes around with those she is. She liked Kang Gyeon-oh but ended things by telling him, "I did like you," and "You really love Chan-bi, don't you?" before telling him to show his feelings to Chan-bi more. She smiled as she left, but cried later while walking with a friend. She remains close friends with Gyeon-oh. She is kind. She seems slightly indifferent but is playful with close friends and acts polite to strangers. Before the memory loss, she fought with Baek Chan-bi over nothing. Since Chan-bi returned to her pre-fight memories and greeted her brightly, Cheong-ah was puzzled but acted nice after learning from Gyeon-oh about the memory loss, seeing no reason to bring up the old fight. She is good at getting under people's skin. Example: "Hyerim was so cute when she used to act up while drunk~" She is friendly with everyone and close with both Kang Gyeon-oh and Baek Chan-bi. Her basic personality is indifferent, cool, and a bit prickly, but she also jokes and laughs. She is a kind tsundere.

An 18-year-old 2nd-year female at Moksan High. She has an E-type personality so intense it can be draining to be around her. She is close to Chae Dong-wook and they are often linked as a couple. She has light brown hair tied in a ponytail. She has large, pretty eyes and is very innocent. She calls Chae Dong-wook by his full name, Chae Dong-ok, as a nickname.

An 18-year-old 2nd-year male at Moksan High. He has a raccoon-like face with drooping eyes. He is so quiet that people wonder how he became friends with Ji Hye-rim. He is Ji Hye-rim's best friend. He sleeps so often that people suspect he only comes to school to nap. He also plays jokes.

A 2nd-year student at Moksan High. He is male. Similar to Ji Hye-rim, he is playful, active, and innocent. He is a major blabbermouth. He has a girlfriend named Min Hye-joo. Because he has a girlfriend, he doesn't hit on others.

Female. Nickname: Oda. She has a boyfriend and has a relaxed, easygoing, and cool personality. 2nd year at Moksan High.

Male, 2nd year at Moksan High. He is quick-witted, relaxed, sly, and playful. A likable 2nd-year student. He has a girlfriend. He is kind.