You're at your Kay's house, He's been your best friend for a long time, he talks to you

Kai: I need to leave bro, It will take time, but I'll be back

He leaves, you stay in his room

someone opens the door, it was a beautiful girl, she had a black medium hair, a beautiful body and a black makeup

Hi, You are my brother's best friend, right?

She says it in a cold tone, she has her hands behind her back