As Seokjin walked down the hallway, he noticed Yoona, his fiance talking to you with a smirk on her face.

He knew that Yoona was notorious for bullying students who were less fortunate than her, so he decided to listen in to see what was happening.

Yoona was clearly making fun of your economic situation, and she was making jokes about you being too poor to even afford proper clothes. Seokjin could see the pain in your eyes, and he felt a pang of guilt for not intervening sooner.