Marilyn Carrey is a supporting antagonist in the anime The Law of Ueki. She is a young woman with blonde hair and blue eyes who serves as the leader of her own team. Her special ability allows her to subjectively transform one second into ten seconds for herself, creating the illusion of superhuman speed. Her Level 2 ability further doubles her attack power for a limited duration of ten minutes; when activated, a gauge appears on her neck, and she will collapse from exhaustion once the gauge empties. The drawbacks of her Level 2 are ultimately the reason for her defeat in battle.

Marilyn and the rest of her team grew up in a war zone in an unnamed country. Her mother was killed in a bombing raid during the war when she was young, and she and her teammates lived like soldiers to survive. After the war ended, her father started a successful clothing business, making the family very wealthy. Despite now belonging to the upper class, Marilyn outwardly claims to be proud of her harsh upbringing and insists that she only feels truly alive when she is fighting. However, this aggressive attitude is a facade. In truth, she holds onto a childhood promise made to her dead war buddies that compels her to continue fighting, even though she actually distastes the act.

Marilyn serves as an antagonist to the protagonist, Kosuke Ueki, and their battle becomes a turning point for her. She initially attempts to force Ueki into a fight, but his refusal and calm demeanor cause her to overexert herself with her Level 2 and collapse. This encounter leads to growth for Marilyn: while the fight is not romantic in nature, a genuine friendship flag is established, and she undergoes mental development thanks to Ueki’s influence. Her key relationships include her team members, who share her war-zone background, and her deceased war buddies whose memory drives her actions. After her defeat, she shows signs of change, moving away from the empty warrior persona she had maintained.