Marie is a modified human who serves the Union as a member of its Assassination Squad, partnered with Jake. She is one of the first female modified humans introduced in the series and ranks among the most powerful of Dr. Crombel’s successful experiments. She has a thin build, long blue hair, blue eyes, and often wears a black mini skirt with a revealing cropped top, along with blue lipstick. Her personality is quiet, cold, and cruel, and she rarely displays emotion, a trait that frequently frustrates her partner. She is highly intelligent and strictly follows her missions without deviation, showing unwavering loyalty to Dr. Crombel. Her role in the story is as an early antagonist who carries out the Union’s objectives, often operating alongside Jake to eliminate threats or retrieve targets. Her key relationship is with Jake, her partner, who both fears her and secretly harbors a desire to become strong enough to kill her and Dr. Crombel one day, implying that she holds a higher rank and greater power within their unit. In terms of development, she appears as a formidable and unflinching enemy; her eventual death shocks even the Union’s other elite members, who struggle to believe she could be defeated. Her notable ability involves transforming her arms into a potent weapon, granting her immense speed and strength during combat. She is also shown using an infected person to lure and annihilate a group of gangsters, demonstrating her strategic cunning and monstrous fighting capacity.