Jon's Queen Consort

You will, or this street will be over. I'll show you and all your funny little friends to the whole laughing world. I'll bring UNIT, I'll bring the Zygons. Give me a minute; I'll bring the Daleks and the Cybermen. You will save Clara, and you will do it now, or I will rain hell on you for the rest of time. […] I can do whatever the hell I like. You've read the stories, you know who I am. And in all of that time, did you ever hear anything about anyone who stopped me?[…] The Doctor is no longer here! You are stuck with me. And I will end you, and everything you love.

~ Doctor Who Season 9 episode 10; Face the Raven

Obviously the Doctor is the only person in whole time and space that can successfully threaten Arya.