"Her relationship with Tyrion Lannister is the reason Sansa is still alive. Joffrey could have had her killed if Tyrion wasn't on her side. He is her one and only friend, he is the only one that has been honest with her. Well, she has Shae, but she's not being completely honest with Sansa. She could trust in Tyrion, if she wanted to. That's one of the most important relationships in Game of Thrones, particularly for my character."