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At the end of the TV episode The Winds of Winter, we see
Cersei sitting and crowned on the iron throne.
What makes them sit there given that
She isn't a Baratheon. Remaining Baratheons, by blood, should then have priority, even if all Robert's, Stannis' and Renly's lines are cut. Cousins probably?
She isn't male, while the series told us for years that women don't sit in that throne (books might say otherwise, though). Season 6 changed that, but there were several hints through the series that this is true. Jaime would be fitting better on the throne than Cersei. It seems to me that in the sexist world of Westerns, they'd better forgive a man some promise rather than let a woman take the lead. See Jon / Sansa in the very same episode.
Even though she killed her accusers, the rumours and reasons why her trial had to take place haven't disappeared with the High Sparrow.
Some people can still see her game. She has The Mountain to fix that but he only stops individuals, not the entire system, doesn't he? At best she'd be a regent, not a queen...