Miwohal Geoya
Eun-Ha, who was bullied in school, is haunted by her past. In college, she meets her worst first love, Gu-Reum, who has hurt her the most in the past. Gu-Reum regrets his actions and tries to apologize to Eun-Ha, but she flatly rejects him.
"Don't apologize to me. I'll always hate you."
(Source: Naver, translated and edited)