Drama friends to lovers

Dramas where ml consider fl just friend ..but fl likes ml... ml has no idea about his feelings for fl ...slowly romance develops...

Or any drama where ml ask help from fl in pursuing her friend (2fl)...where as fl likes ml...

A Piece of Your Mind.  FL likes ML, but he doesn't know it.   How he finds out is quite original.

It's a great drama, one of my favorites.  But you have to give it some time. The first couple of episodes are confusing, but the confusion is generally cleared up by episode 3. 

https://mydramalist.com/38491-half-of-half