M-24 is a large, bald, muscular man with purplish-pink skin and an angular jaw. He typically wears a black fedora, a gray turtleneck sweater, a black jacket, and dark pants. He was one of the first hundred humans subjected to experimentation by the Union, designated M-24. Like M-21, he is considered a failed experiment and relies on pills supplied by the Union to prevent his body from deteriorating.

Initially, M-24 appears cold and cruel, but he later reveals a compassionate and caring nature. He shares an exceptionally close bond with M-21, as the two are the only survivors of their experimental group. Together, they attempt to learn the names of their lost comrades. M-24 expresses a desire for M-21 to call him “older brother,” suggesting that before his transformation he had younger siblings. His motivation ultimately shifts from following Union orders to protecting others, particularly the students Shinwoo, Ikhan, and Yuna.

In the story of Noblesse: Awakening, M-24 serves as an antagonist working under Jake and Marie, but he secretly plans to betray the Union in order to free himself and M-21. When Jake begins brutally beating Shinwoo, M-24 can no longer stand by and attacks Jake in an attempt to buy time for the students to escape. He is killed by Jake in this self-sacrificial act.

M-24 possesses minor mind-control abilities, a side effect of the Union’s experiments. He uses this power to help M-21 learn to resist mind control, repeatedly testing him. He can also produce and control infected beings. Beyond these abilities, his enhanced physique makes him a formidable combatant, though he is ultimately outmatched by stronger enemies.