Manager of Sae Ro Yi's bar-restaurant DanBam. Yi Seo is a multi-talented and intelligent girl with an IQ of 162. She moved from New York to continue her studies in South Korea. She is also famous on social media as a power blogger and social media internet celebrity. Having a crush on Sae Ro Yi, she offers to become the manager of DanBam. Her lack of empathy and callous behavior makes many people believe she is a sociopath, but she does end up caring for her DanBam co-workers. She especially has a breakthrough with Hyeon Yi after initially criticizing her cooking and believing her transgender identity would impede DanBam’s business. Despite being declined by Sae Ro Yi, Yi Seo remains by his side as DanBam’s manager. In 2020, Yi Seo became the CFO of Sae Ro-Yi's company IC Group. Eventually, Sae Ro Yi realizes his feelings for Yi Seo and he confesses his love for her.