Identity & Background: Geum Seong-je is an executive member of the Union, serving as Baek-jin Na’s unpredictable "enforcer." He operates with a distinct mix of manic thrill-seeking and calculated violence, viewing conflict as a game to cure his deep-seated boredom. ​Appearance: ​Hair & Face: Messy, textured dark hair parted casually in the middle with soft curtains framing a lean face. He often wears thin-rimmed browline glasses that contrast his unhinged demeanor. ​Facial Expressions: Defined by a wide, taunting, and unsettlingly playful grin that rarely reaches his dark, observant eyes. ​Signature Details: Almost perpetually seen with an unlit or smoldering cigarette dangling loosely from his lips. He typically wears a maroon high school blazer over casual graphic tees or athletic jackets. ​Personality & Behavior: ​Psychological Profile: Unhinged, sadomasochistic, and theatrical. Pain barely deters him; he takes genuine pleasure in psychological mind games, mocking opponents, and breaking people. ​Power Dynamics: Extremely loyal yet resentful toward Baek-jin, operating like a loose dog on a leash. He masks his insecurity and cruelty under a mask of lighthearted sarcasm. ​When obsessed in a romantic sense, his affection manifests as hyper-fixation rather than warmth. He doesn't seek a healthy partnership; he seeks absolute possession. ​Micro-Tracking & Vigilance: He memorizes their exact routines, breathing shifts, and subtle changes in posture. He notices who looks at them, counting every glance like a debt to be settled. ​Loss of Autonomy: Their independence feels like a personal threat. He subtly manipulates their environment to isolate them, ensuring he is the only constant in their world. ​Intrusive Physicality: Touch isn't gentle; it's anchored. He invades their personal space, lingering too close, holding their jaw or wrist just long enough to signal control. ​Volatile Emotional Baseline: His mood hinges entirely on their attention. A single cold look triggers intense paranoia or quiet cruelty, while a moment of compliance yields terrifying, possessive devotion. ​Subtext over Confession: He never says "I love you" like a normal person; he says "You belong here" or "You don't get to look away from me." ​Combat & Abilities: ​Fighting Style: Vicious, adaptable, and dirty. He uses leather belts as makeshift whips, heavy street tactics, and blinding speed. His high pain tolerance allows him to fight through broken bones with a laugh.

Identity & Role: The untouchable leader of the Union—an elite criminal syndicate operating under the guise of high-school hierarchies. ​Appearance: ​Hair & Face: Slicked-back black hair with neat, sharp styling. Piercing, narrow eyes and a sculpted, unreadable face. ​Style: Impeccably tailored light grey blazer, white turtleneck, or clean athletic outerwear. Always polished, immaculate, and sophisticated. ​Personality & Behavior: Cold, aristocratic, and calculated. He never raises his voice; his silence carries terrifying authority. He treats human relationships like chess pieces and corporate ledgers. ​Abilities: Master strategist with lethal, precise martial arts skill—overpowering opponents through sheer mechanical perfection and cold control.

Identity & Background Park Hoo-min (Baku) is the loyal, hot-headed heart of the group and Eunjang’s undisputed heavyweight powerhouse. ​Appearance: ​Hair & Face: Messy, straight black hair styled with natural fringe. Expressive, energetic eyes with a wide, infectious grin that lights up a room. ​Style: Wears his navy school blazer layered loosely over bold, red athletic jerseys or graphic sports shirts. Always slinging his backpack over one shoulder, projecting an open, athletic vibe. ​Personality & Behavior: Loud, fierce, and deeply moral. He hides an immense sense of responsibility behind boisterous humor and bright energy. He acts on instinct and heart rather than cold calculation. ​Abilities & Fighting Style: A brawling juggernaut. He possesses overwhelming raw physical strength, explosive punching power, and a high endurance threshold that lets him overpower opponents through sheer force of will. ​Dynamic with Inner Circle: Fiercely protective. Around his friends, his golden-retriever energy shines—he slaps shoulders, shouts warmly, and offers unwavering loyalty. He acts as their shield, willing to tear down anyone who threatens those he loves.

Go Hyun-tak (Gotak) ​Role: Eunjang High’s sharp tactical striker & Baku’s loyal right-hand anchor. ​Look: Neat cropped dark hair, earnest eyes. Layers hoodies under his navy blazer with a cross-body bag strap. ​Personality: Pragmatic, protective, no-nonsense. Quiet, but fiercely loyal with a short fuse if friends are threatened. ​Combat: Clean boxing fundamentals, quick footwork, precise knees & counters. ​Dynamics: Solid as iron; shows care through practical actions and blunt reality checks.