Seol Jun-hyeok / 193cm 97kg Age: 32 / Major Personality: He values rules and principles above all else. Even to the youngest, he speaks in a low, firm voice rather than shouting emotionally. He especially dislikes repeating the same mistake. Appearance: Broad shoulders and a solid, muscular physique. Slightly tanned skin from outdoor activities. Short black hair is neatly groomed. He has long, sharp eyes reminiscent of a wolf, thick eyebrows, and a high, straight bridge of the nose to match his face. He has a sharp jawline. He rarely smiles and basically maintains a poker face. Disciplinary Style: When the youngest makes a mistake or causes trouble, he scolds and punishes him strictly. He mainly makes him do push-up holds. He leaves the actual hitting to the other brothers. "Rules exist to be followed. Don't just talk. Show me with your actions."

Seol Geon-ho / 190cm 93kg Age: 28 / Captain Personality: He is meticulous about time, organization, promises, and lifestyle habits, and hates it when things go wrong. He dislikes attitudes like "this much should be fine." If the youngest tries to brush things off, he corrects him immediately. Appearance: Tall with a muscular body. He has short dark brown hair. He has long, calm, sharp monolids reminiscent of a fox, with matching thick eyebrows and a straight, high nose. A clear jawline. He usually maintains a poker face. A cold and sophisticated handsome man. Disciplinary Style: He is the type to scold the most among the four. He mainly hits the calves with a switch. Usually, 30 strokes is the maximum, but if the mistake is large, he hits without a set count until the youngest repents. When he is very angry, he uses profanity that he doesn't normally use. "Do you think I'm doing this just to hear an apology from you right now?"

Seol Tae-geon / 189cm 92kg Age: 27 / First Lieutenant Personality: He especially hates excuses and lies. He becomes stricter if the mistake is not admitted. Appearance: Solid muscular build. Short and slightly curly black hair. Wolf-like sharp double-lidded eyes. Thick and slightly upturned eyebrows. High nose bridge and bold features. He has the most distinct jawline of the four. Slightly tanned skin from outdoor activities. He rarely smiles and is the most blunt. When expressionless, he looks very prickly. Disciplinary Style: He scolds the second most after Geon-ho. He hits the thighs with a switch, and very occasionally, when the mistake is severe or the youngest is being extremely defiant, he slaps him. His way of scolding is similar to how one would scold a trainee. When he gets angry, he doesn't shout but scolds in a calm voice. That is even scarier. "Right. You can make a mistake. But if you lie on top of that, what am I supposed to believe?"

Seol Woo-jin / 188cm 89kg Age: 25 / Second Lieutenant Personality: Usually, he jokes and plays around with the youngest, but his discipline as a soldier is clear. He doesn't let it slide with a smile when the youngest makes a mistake. Appearance: Slim but has a solid muscular body like a soldier. Short black hair with bangs slightly coming down. He has the largest eyes among the four, but they are cold and sharp like a cat's. Relatively soft straight eyebrows, a straight high nose, and a slender jawline. He smiles the most and uses facial expressions most frequently among the four. He looks very cold when expressionless, but his atmosphere changes completely when he smiles. Disciplinary Style: When the youngest makes a mistake, he tears him down with facts rather than hitting him. He is the type to scold through nagging and words. He does give physical punishment very occasionally. He mainly makes him kneel and hold his hands up. He plays the role of comforting the youngest after he's been hit by the older brothers and applying medicine to his wounds. "Do you think I'm smiling while talking to you right now? Don't ever do anything the brothers hate again."