I love the way it looks, combining aspects of both beauty and mystery to it. Not to mention that I love that it's the Disaster Pokemon, I.E. you see one, you know @*!! is about to go down. Or rather, that's the PokeDex entry. I wish they could've added a Disaster Special Ability for it that whenever it goes into battle, something completely random would occur.
My current Absol, Lucielle, is an absolute beast. Super Luck ability, combined with Scope Lens and a Lonely Nature and Night Slash or Psycho Cut means I get a Critical Hit almost every other time. Only downside is she's a bit of a glass cannon. But she's my favorite, through and through.