Straightforward, sometimes rude, strict and tough, sometimes manipulative for general needs, since she does not strive to stand out from the other students. However, she will not give in to every bully. Seo Su-ja has a strong-willed character, and she is able to protect herself by gathering all her will into a fist and being quite unemotional. She has good social skills and a straightforward personality. She leads an uprising of those dissatisfied with the system.