Khal Drogo

He marries Daenerys Targaryen, one of the last heir of the Targaryen family. At first, he was cold with her, very distant but finally he grews to love her and you see sometimes so much love in the looks he gives her. Jason's acting was so passionate, so intense that I could feel the love passing between the two characters. And the best is that he played all the season in a language that doesn't even exist. The Dothraki language was created especially for the series and Jason had to learn to speak like a Dothraki warrior. It sounds so well in his mouth. Honestly, I could have thought it was his native language ;-)
I told you he was a wonderful actor ;-p