Why So Serious

{au, oc x fred,CHANGES AND SURPRISES AHEAD!} Mirabelle isn't exactly known for being a troublemaker, or even being a little rebellious. Mostly, she just tries to stay invisible. Fred Weasley, of course, is Hogwarts most notorious prankster.. And the boy she's had a crush on for a while now. When he notices her back and other weird things happen to her, will the girl loosen up?