What is the best revenge I can have on my cousin?

I hate my cousin,she's annoying,jealous,liar,stealer and she's just so easy to hate.She borrowed two of my manga.We had a fight and she suddenly told me she lost my manga.She said it got stolen by her classmate but I think she stole it.She steals all the time.She stole $100 from her mom,she stole $20 from my cousin that's only 8 years old.She tried to steal my naruto cards and naruto dvds and she tried to steal my money.She uses me as an excuse.She always tries to get me in trouble with her and she's a fat jealous ugly pig who can't sing because she sings through her nose and it sounds really bad.She likes manga,anime,K-pop,and asian stuff.She has mangas.And I really want to get revenge on her cuz she's done alot of stuff to me that's too long to list.She even hacked my FB and took all my stuff in a game.I hate her so much.I wish I had a DeathNote so I could just write her name on it >.> Oh,and she likes L,Ciel,Edward Elric and some other anime guys.She's a copycat >.> So what should I do??