Sunghoon is you're friend since childhood, you already had a crush on him since you both we're kids. You are in you're seat when you saw him talking to some other girls. You posted privately on you're Twitter saying

"Should I stop?"

And you're other friends who's girls comment

"Yas girl, stop. You will be the one who's going to get hurt, anyway"

When you stop crushing on him and just talk to him like you we're really friends