Hmm... probably Sesshomaru from InuYasha, or Yugi/Yami annd Ryou/Bakura from Yu-Gi-Oh(namely season 0) AND Marik and Malikheartheartheartheartheartheart
I can't choose because I like so many! TTATT
I'll just post an Anime Love Meme I did a while back. XD
And I love more too but there wasn't room to put anymore XD
Can't forget about Sebastian from Kuroshitsuji either :O
(By the way, this meme is on my DA if you wanna check it out :3)