Qwerty's Things

I can't remember the title of this shoujo manhwa but all I can remember is that, the fl has long black hair and I think she has some powers? I can't remember what it is specifically but it's something special. Then the ml has blond hair and as far as I can remember is that he didn't like her at first? Then somewhat became obsessed to after a few chapters? Also I think this manhwa is already completed because I remember I want to read it if I have the time but now I can't remember the name