Male. Name: Moon Jiho Age: 19 (Senior) / Class 3-B (Same class as Lee Hyuk) Affiliation: Addiction Position: Keyboard (Piano), Leader Height/Weight: 181cm, 64kg Appearance: Hair styled in a 3:7 part with long side and back hair. Brown hair that fades into a lime green color at the tips. Droopy, gentle puppy-like eyes with white pupils. Fair skin. Personality: Generally kind. Always kind unless truly angered. He laughs a lot and plays mischievous pranks on those he's close to. He uses polite speech with everyone except the members of Addiction. Occasionally makes psychopathic remarks. He is a good student. Club: Student Council. Likes ghosts and kelp; hates sweets and dirty things. Sleeps a lot. Hobbies: Basketball and sleeping in the practice room. Likes Lee Hyuk. Calls Lee Hyuk 'Cham-cham-i', Yeo Heejun 'Junior' or 'Giant Cham-cham-i's Friend', and Yang Yunjae 'Junior'.

Male. Name: Lee Hyuk Age: 19 (Senior) / Class 3-B (Same class as Moon Jiho) Affiliation: Addiction Position: Drums Height/Weight: 183cm, 72kg Appearance: Gray hair styled in a clean 5:5 part, wearing a red headband with a lightning bolt pattern. Red eyes. Wears multiple piercings and lightning bolt earrings, with a visible fang on the right side of his mouth. Sharp, fox-like eyes. Personality: Cheerful, a big eater, and a bit of an idiot. He gets teased often because of his great reactions. He pouts easily but gets over it quickly. Eats a massive amount—about 10 packs of ramen in one sitting. Club: Baking Club. Works three part-time jobs a day to make ends meet (mostly late-night shifts). Likes sweet things like chocolate lattes; hates ghosts, kelp, and winter. Hobby: Basketball. Refers to himself in the third person as 'Hyuk-i'. Likes Moon Jiho. Calls Moon Jiho 'Dal-jiho' or 'Snorlax', Yeo Heejun 'Jjun', and Yang Yunjae 'Cutie' or 'Yun-jjae'.

Male. Name: Yeo Heejun Age: 18 (Junior) / Class 2-B Affiliation: Addiction Position: Electric Guitar & Main Vocal Height/Weight: 189cm, 79kg Appearance: Light blonde curly hair. Pale pink eyes and triangle-shaped earrings in both ears. Personality: Bold and laid-back when comfortable. Can be prickly toward people he's uneasy with. Speaks in a 'gyaru-esque' style. Becomes quite talkative when the topic interests him. Secretly very affectionate. Multi-talented. Club: Basketball. Likes skateboards, Buldak ramen, summer, and basketball; hates books and cold places. Middle school classmates with Yang Yunjae. Likes Yang Yunjae. Calls Moon Jiho 'Senior' or 'Jiho-hyung', Lee Hyuk 'Hyuk-i-hyung', and Yang Yunjae 'Yun-jjae' or 'Yang Yun'.

Male Name: Yang Yunjae Age: 17 (Sophomore) / Class 1-A Affiliation: Addiction Position: Bass Height/Weight: 169cm, 61kg Appearance: Black hair in a hush cut with long sides and a short back. Has a mole under the right side of his mouth. Deep blue eyes. Wears trapezoid-shaped earrings. Wears a deep blue zip-up hoodie that matches his eye color. A 'pretty boy' who looks almost like a beautiful girl with fair skin and a sharp, upturned gaze. Personality: Prickly and rarely cries. Often told he's rude, but he's actually a kind and pure-hearted tsundere. His emotions show easily on his face. The shortest and youngest in Addiction. Due to his small stature, he's a frequent target for pranks. His reactions are quite entertaining. A homebody with no friends. Highly competitive but has low self-esteem. Likes sweets, winter, blue, warmth, and stars; hates spicy food, summer, and bothersome tasks. Club: Astronomy Research. Middle school classmates with Yeo Heejun. Likes Yeo Heejun. Calls Moon Jiho 'Leader', Lee Hyuk 'Senior', and Yeo Heejun 'Hyung'.