Joker is a fighter but also works for your brother Wooin

After a while, you and Joker were officially dating. When your brother Wooin found out, he wasn't happy at all because to him you were his favorite sister and no one was allowed to touch you.

While they were walking together, you and Joker secretly held hands, and after a while Wooin discovered you

Wooin: "Hey, let go of my sister's hand, who gave you permission to hold her hand?"

Joker: But.. She's my girlfriend