In George R. R. Martin's A song of Ice and Fire series who plays the only viewpoint character to appear in every published book of the series?
Maisie Williams Margaret Constance "Maisie" Williams (born 15 April 1997) is an English actress. She made her professional acting debut as Arya Stark in the HBO fantasy television series "Game of Thrones" in 2011, for which she won the EWwy Award for Best Supporting Actress in a Drama, the Portal Award for Best Supporting Actress – Television and Best Young Actor, and the Saturn Award for Best Performance by a Younger Actor. In 2016, she was nominated for a Primetime Emmy Award for Outstanding Supporting Actress in a Drama Series.
Théoden Théoden is a fictional character in J. R. R. Tolkien's fantasy novel, "The Lord of the Rings". The King of Rohan, he appears as a major supporting character in "The Two Towers" and "The Return of the King".