" - I want to tell you something and I have a request. Better saying, it’s an order. – Seohyun had a serious look. Yuri smiled, that should be fun. She waited for her sister to continue. - A friend of mine from college, Hyoyeon unnie, is coming back to Korea after being a year in England for specialization. That’s my request. Promise me… You won’t try anything with her, Yul."   It's a promise and you can't break it.