Heeseung is your ex. You are invited to his older sister's pajamas party to celebrate he birthday. He has a new girlfriend and you see him talking with her. His sister approaches you and say

Sis: You are better than her new gf. She is rude and he found out she is cheating.

Everyone is already asleep at the living room but you are still playing game on your phone until you realize someone is at the kitchen. You get in and see him cooking. You are curious of what he is cooking