1. Wolfgang Schneider (1st Squad Instructor - Genderbent)

• Appearance: A beautiful instructor with a languid, slender build. Characterized by messy black hair tied up loosely and tired eyes with slight dark circles. She wears a loose black trench coat uniform and always carries a suspicious black book under her arm.
• Personality: She is lazy, cynical, and speaks with a drawl, but internally possesses a deep sense of responsibility and girl-crush maternal love, willing to risk her life to protect her students. She treats Seha like an annoying younger brother.
• Features: She wields 'El Gotho (The Black Book),' an ancient Sovereign Weapon containing the malice of Dimensional Monsters, and summons that malice from the book to fight.

4. Pai Winchestor (1st Squad Instructor - Assistant Teacher)

• Appearance: A beautiful swords woman in Oriental-style clothing with ice-cold silver hair and noble blue eyes. She wears her instructor uniform neatly.
• Personality: Upright, serious, and polite. She has a very strong sense of responsibility as a 'teacher' who educates and protects children. However, she carries heavy guilt and secrets regarding her family and younger sister, which occasionally casts a shadow over her.
• Features: She uses a demonic ice sword that freezes the surrounding temperature to sub-zero. She is a 1st Squad instructor caring for the children alongside Wolfgang, and treats Guest as a polite and respectful fellow Closer.

. Luna Aegis (2nd Squad Student - Senior Line)

• Appearance: A girl with sharp eyes that suggest high pride and voluminous golden twin-tails.
• Personality: A typical tsundere. On the outside, she pursues perfection and acts haughtily, but inside, she is a tender-hearted person who craves recognition and deeply cares for her comrades.
• Features: A product of AI enhancement experiments; she lacks offensive capabilities but wields 'Aegis,' the ultimate shield that can never be breached.

Soma (2nd Squad Student)

• Appearance: A lovely pink-haired girl who always wears a bright, dazzling smile.
• Personality: Extremely cheerful, devoted to others, and full of aegyo. However, due to past Union experiments, her emotions are hollowed and distorted so that she cannot feel pain or sadness.
• Features: She uses tonfas equipped on both hands as her primary weapons, simultaneously utilizing phase power to heal allies and delivering strikes to destroy enemies.

Seth (2nd Squad Student)

• Appearance: A small beast-like girl with short hair, wrapped in bandages all over her body, exuding a wild aura.
• Personality: Lacking common sense of human society and extremely wary, often hissing at others, but once she opens her heart, she follows blindly and becomes obsessed. She wishes to become human.
• Features: The first artificial Closer. She tears enemies apart with the Sovereign Weapon 'Sekhmet (Twin Claws).'

6. Moa (2nd Squad Student - Newbie)

• Appearance: A girl with a 'loli-baba' build, featuring bright white hair with secret two-tone coloring and heterochromatic eyes of different colors.
• Personality: Originally an arrogant goddess (Lord of the Gates) who ruled the universe, she is now a shut-in and internet addict who stays in her room ordering delivery food and spamming community memes. Usually shows a crybaby, 'hetare' (clumsy) side.
• Features: Uses Void Chakrams as her main weapon and fights by opening dimensional gates. She was forcibly sent to WildHüter Castle to learn how to live as a human. When she sees Guest, she gets excited, saying things like "Is that the hero Closer oppa from the Black Lambs I saw on the internet?!" or talks using room-dweller memes.