Mari (Kor. 마리) was a modified human who served the Union as a member of its Assassination Squad where she was partnered with Jake. She was the first female modified human shown within the series as well as one of the two main antagonists of Season 1.
Mari was a thin, young woman with blue eyes and long blue hair. She wore blue lipstick and a black mini skirt with a revealing black (or blue) cropped top.
Mari was very intelligent, always strictly followed her missions, and was loyal to Dr. Crombel. She rarely displayed emotion and was usually taciturn, which frequently irritated Jake, her partner.
Although she was often overshadowed by Jake's frequently outrageous actions due to her stoic, avoid-trouble-if-possible disposition, she had a very cold and contemptuous nature, and harboured arrogant superiority complex toward M-21 and M-24, seeing them as unworthy "trash". When she died, everyone in the Union, including the members of the DA-5, showed surprise. They all found it hard to believe that she could have been killed.
Mari was one of the first female experiments seen in the series. She was seen as a powerful, successful experiment, compared to M-21 and M-24, and was modified by Dr. Crombel. It is implied that Mari was more powerful than her partner Jake, which meant that she held a higher rank and a commanding capability. As a member of the Assassination Squad, she was assigned to assess Jake as a squad candidate.
The Human World Arc
The Assassination Squad
Mari and Jake arrive at South Korea as Dr. Crombel's bodyguards. They check up on M-21 and M-24 and scold them for no progression on their mission. While Jake creates chaos in the hospital for amusement, Mari remains silent. They find the Infected who tells informs them about the alive witnesses (the children) and the location of one of them (Shinwoo). The three of them are on their way to Shinwoo's apartment but meet Frankenstein on the way who bargains a fight for info. Mari stops Frankenstein from killing Jake and decides to retreat rather than answer his questions.
Mari takes Jake to the local lab as his wounds aren't healing. As Dr. Crombel is there, she reports the presence of this strange blond man to him. Dr. Crombel orders her to capture the strange sample and so she starts investigating on her own. She pins out the people who stole the casket to find out the identity of the blond. Not getting any info from the interrogation, she kills all of the thieves. After failing to find the sample, Mari is informed by Jake another piece of news he received from the Infected ~ M-21 and M-24 had lured out the children once before. So, they decide to use them to lure out and kidnap the children once again.
A New Plan
This time, Mari and Jake separate the duo and Mari keeps M-21 along with her (this renders M-21 unable to warn Frankenstein). As the children are returning from the Principal's house, the Infected recognises them and both Jake and Mari realise they've got their prey. However, M-21 and M-24 knock down the children unconscious to prevent Jake from hurting them. M-21 mentions one of the kids is missing and suggests to use the others to call him out. Mari assumes it might have something to do with the blond guy and assents to his proposal.
Mari takes M-21 with her to wait for the arrival of the remaining kid outside. While inside, M-24 steps up to face Jake in order to save the children and breaks his communication device. As M-21 is busy trying to communicate with his partner, Mari suddenly attacks him. However, much to her surprise, the attack is dodged and M-21 reveals his partial transformation. Mari starts to get serious but Raizel and Frankenstein arrive just on time. After Raizel goes to save the children with M-21 guiding the way, Frankenstein faces Mari.
Mari fully transforms to fight Frankenstein. The fight drags on for a while until Raizel commands Frankenstein using telepathy to eliminate the enemy standing before him. With his seal undone, Frankenstein rejoices and lets Mari know why her wounds have stopped regenerating ~ it's because everything about them (modified humans) has started from him. Mari, clearly shocked and scared at the sudden statement and continuously increasing malevolent aura, asks Frankenstein what he meant but gets pierced with dark projectiles in reply. With her death, the mind link she had with Dr. Crombel gets cut.
Mari was a strong, enhanced modified human as a part of the Assassination Squad. She could effortlessly take out a gang by herself. Jake initially complied with her decision for her being the superior. Despite her strength, the DA-5 rebuked her skills by saying that she was very weak, especially in combat, further showing the difference in strength between Mari and the members of the DA-5.
She has been shown to have the ability to transform her arms which become black with two spikes coming out of each arm. Also, vein-like aura appears throughout her arms when she transforms. Mari gains immense speed and strength in this transformed state. It is implied that she was even more powerful than Jake, for he had vowed to kill her and Dr. Crombel one day, but not until he became stronger. Jake was also afraid of her, further attesting to Mari's immense strength. She was, however, killed by Frankenstein.