I can't see Cersei bowing out and leaving King's Landing like that though. She's power hungry. She's more liable to burn that place down and go up in flames along with it before leaving. Plus, she's supposed to be choked out by the Valinquar like Maggy the Frog had told her in regards to her prophecy. She's suppose to lose all of her children. so far, Tommen remains. Valinquar translates to "Little Brother" possibly even "Little Sister" I think. So I think it's possible she gets choked out by one of three people.

 

Jaime Lannister - Even though they're twins. She was birthed before him. In the show they seem to give off this idea that Jaime loves her. Which he does. But in the books it's more complicated and he's grown suspicious and aggravated with her off and on. That's based on the 5th book though so maybe his mind changes again about her in the 6th book before he maybe chokes her out.

 

Tommen Baratheon - The prophecy said she'd lose all of her children but it didn't say before or after she gets choked out. It could be possible Tommen being the "little brother" of his siblings ends up killing her.

 

Arya Stark - Again, like Tommen, she's the "Little Sister" of the Starks.

 

I honestly think and it hope it'll be Tommen killing her. Just because he's been so weak, manipulated and light hearted. It would be a bittersweet ending for him to kill his corrupt mother.

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