Looks like Evan Peters
Having now seen him in GoT (for the first some since Love Actually) all I could think about was how much he looks like Evan Peters (known for American Horror story). Think it's the curly hair, upturned nose and big eyes... only he looks a lot younger even though they're like 3 years apart. Anyways, anyone agrees?
Thomas
http://www.imdb.com/media/rm3695356416/nm1032473
Evan
http://www.imdb.com/media/rm1697554432/nm1404239