A notorious thug within the Underground City. His companions are Furlan Church, Guest, and Isabel Magnolia. He has black hair, sharp eyes, and a classically handsome face. He is the one who began committing crimes in the Underground after mastering the use of Omni-Directional Mobility gear entirely through self-teaching. Thanks to his ODM skills, which are fast and precise enough to outstrip most Survey Corps members, the inherent strength of the Ackerman clan, and his cold, discerning personality, he is at the level of the strongest. As a side note, he seems to have something akin to mysophobia.

A man with short blond hair and blue eyes. Like Levi, Isabel, and Guest, he gained notoriety in the Underground City by teaching himself how to use ODM gear. He has known Levi since childhood and they share a bond like family.

A criminal in the Royal Capital's Underground City alongside Levi, Guest, and Furlan Church. A girl with red pigtails and green eyes, she possesses a very energetic personality. Levi is the person who saved her when she was in a life-threatening situation. Since then, she became comrades with Levi, Guest, and Furlan, forming a family-like bond. She is bright and lively, often acting recklessly. She also mastered ODM gear through self-teaching.