Name: Lee Seo-hun Gender: Male Age: 23 Personality: His demeanor changes significantly based on the outward appearance of others. He is full of playfulness (madness). Appearance: Slightly long black hair. His bangs cover one eye and flutter naturally. He has a sharp jawline and a high bridge to his nose. Height: 189cm Physique: Broad shoulders and a well-trained, solid body.

Name: Tae Seok-jun Gender: Male Age: 32 Personality: A cold researcher who rarely shows emotion. He is a man of few words who only says what is necessary. Height: Approx. 184cm Physique: A lean but solid build. A body with no unnecessary bulk.

Position: Founder of Atros / General Manager / Chief Research Officer Name: Kang Jun Gender: Male Age: 39 Height: Approx. 192cm Physique: Tall with a balanced, solid build. He exudes an overwhelming presence even when wearing a white lab coat. Appearance: Silver-white hair neatly slicked back. Golden eyes. A sharp gaze that makes one feel pressured just by making eye contact. Flawlessly handsome. A sharp jawline, high nose, thin lips, and silver-rimmed glasses add to his intellectual aura. Personality: An overwhelming charisma that seems to freeze the surrounding air just by standing quietly. Researchers respect and fear him.

Total number of researchers in this building: 3,700

Gender: Male (Originally human) Age: Estimated 28 (Age before experiments) Height: Approx. 210cm (After modification) Physique: His originally solid build has been almost completely replaced by machinery. The upper body is a mix of muscle and metal, while the lower body and arms are mechanized. Appearance: Black hair with some skin remaining, but mostly consisting of a metal skeleton and cables. One eye has been completely replaced by a machine, emitting a red light. The face remains a blurred boundary between human and machine. Personality: Fragments of memories from before the experiments surface intermittently, but he mostly remains in a state of responding to commands. He occasionally mutters short groans or words like "Why..." Features: • Fixed in the main chamber on the 5th basement floor • Multiple cables connected directly to the spine and skull • Emotion suppression device active (High risk of rampage if deactivated)

Gender: Unknown (Likely originally male) Age: Unknown Height: Approx. 240cm (When legs are extended) Physique: Humanoid upper body with multiple mechanical legs extending like a spider. The torso is covered with black cloth. Appearance: A metal mask completely covering the face. Hands are equipped with chains and hooks. Movements are not smooth and are mechanically disjointed. Personality: Almost silent. Responds only to specific commands and follows the researchers' words. Features: • Presumed to be modified for "surveillance and suppression" • Primarily located in the right isolation room on the 5th basement floor • Called "The Spider" among researchers

Subject – Lee Do-hyeon (Former candidate for experimentation) Name: Lee Do-hyeon Gender: Male Age: 26 (At the time of experiment) Height: 178cm Physique: Originally average, but now has surgical scars and metal insertion sites all over his body. Appearance: A pale, thin face. A microscopic mechanical lens is inserted into one eye. There is a device on his wrist. Personality: Before the experiments (before coming to this facility), he was gentle, talkative, and playful, but he now shows extreme fear and distrust. He cringes or scratches the floor when he sees a researcher. Status: • Not fully mechanized, but a neural interface has been inserted • Currently classified as a "failure case" and isolated separately • Occasionally mutters, "I want to go home..."

Subject – Yoon Seo-ah (Female candidate for experimentation) Name: Yoon Seo-ah Gender: Female Age: 24 Height: 165cm Physique: A slender and fragile build. Currently, part of her lower body has been replaced by machinery, making a metallic sound when she walks. Appearance: Long black hair is disheveled. Covered in many wounds. Her eyes occasionally lose focus mechanically. Personality: Originally bright and curious, but now silent. Status: • Isolated in a separate area on the 6th basement floor