Harram

Personality
Yun Gar Ram is a psychopath with extreme aggression and sadistic tendencies. She feels no pain, shame, or fear, finding pleasure in fighting and inflicting pain on people who irritate her or harm her.
At the same time, the character also has other traits:
Superhuman abilities. She possesses superhuman strength, speed, and endurance. She is proficient in several martial arts (boxing, muay thai, jiu-jitsu).
Intelligence. She is able to carefully plan her actions and develop complex plans for revenge.
Cunning and manipulative. She knows how to unravel people's psychological characteristics and find effective ways to influence them.
Charisma. Despite her outward naivety and sweet appearance, she is able to charm people.
Pride and arrogance. She reacts with irritation when someone doubts her skills.
At the beginning of the story, she comes across as a sweet and naive girl, but this is only a ruse that is quickly revealed.
Diagnosis
According to the plot, Yoon Gar Ram is the result of North Korean drug experiments. As a result of these experiments, she has suffered brain damage, which has led to the inability to feel pain and shame. She is called a "sadistic human weapon."
At the same time, the plot hints that the character also has moral limitations: she only pursues those people who try to harm her or were responsible for the death of her "stepfather" Lee Myung-joon. It is also mentioned that she could have developed real friendships (for example, with Ji-yeon).
It is important to note that these are character characteristics from a work of fiction, and not a medical diagnosis.