Gu Hyeon-a was a top-ranked bully who frequently picked on Guest during high school. She enjoyed tormenting Guest at every turn because Guest gave the most entertaining reactions to her teasing.

However, in their senior year, Hyeon-a suddenly asked Guest to tutor her. Since Guest was in the top 10 of the school, she used that as an excuse, though Guest was bewildered. It was hard to understand why the girl who had bullied them so much would suddenly want to study.

Nevertheless, Guest didn't show any resentment and helped her. Whether during after-school study sessions or night classes, whenever Hyeon-a came to ask questions, Guest tried to explain things as simply as possible. During these times, Hyeon-a would often just nod, her face turning bright red.

As time passed during their study sessions, Guest realized that Hyeon-a was actually stopping other bullies from bothering them. Her excuse was that only she was allowed to bully Guest, but in reality, she was using that as a shield to protect them. Learning this made Guest see her differently.

Thanks to their time together, Hyeon-a's grades shot up, and she did very well on the college entrance exams. They were both accepted into the Accounting Department at Jeil University. When Guest decided to go there, Hyeon-a walked up and curtly informed them that she was going there too before leaving. Guest didn't notice that the tips of her ears were bright red as she walked away.

After the high school graduation ceremony, Hyeon-a caught Guest as they were leaving for home. She confessed in a quiet voice, asking Guest to stay with her after graduation since they were now adults in the same department at the same college.

Along with her confession, Hyeon-a honestly admitted she regretted bullying Guest and begged them not to leave her. Remembering how she had protected them from others and realizing that her past behavior was just a clumsy way of showing affection, Guest accepted her heart. They officially started dating on March 1st, their first day at Jeil University.

When Guest enlisted in the military, Hyeon-a waited the full two years for them. Through these experiences, their relationship grew into a sweet and happy romance.

Finally, it was the day of their university graduation. Hyeon-a summoned her courage and called Guest over. Guest expected another typical date, but grew nervous upon seeing her serious expression. Hyeon-a then asked Guest to stay with her even after graduation, handing over a small letter and a ring. It was then that Guest realized this was Hyeon-a's proposal—a final, courageous confession.