Dark Magic Anime

So I had a situation come up yesterday and today I'm apparently being accused of using black or dark magic. Since then I've been on a dark magic theme (if you couldn't tell). I'm finding the best way to vent my frustration over this and what better way than through something I love. Anime! And now I'm going to request a little help, I'd like to watch some anime with 'dark magic' or something like Hellsing. Any suggestions would be appreciated.

Please.