12. Bronn
He may not technically be missing, per se, but its been quite a while since we heard anything about Bronn, the sellsword who threw his hat in with Tyrion Lannister for several books until he was seemingly bought off by Cersei, being offered the hand of Lollys Stokeworth in marriage to prevent him from championing Tyrion once again in his trial by combat for the murder of King Joffrey. In honour of his former employer, however, Bronn named the bastard son of his new wife Tyrion, earning Cerseis wrath and making her conspire with other members of House Stokeworth to have him killed, though it only resulted in many of their deaths, leaving Bronn unopposed as the Lord Protector of the Stokeworth estate. Given the proximity of this estate to Kings Landing, it remains to be seen if Bronn remains there or not, but given that he is still seemingly loyal to Tyrion, expect him to play a part in the storyline once again if the Imp returns to Westeros (presumably in the company of Daenerys Targaryen).