Jaime Lannister is an interesting antihero to follow on Game of Thrones. Fans root for him, and he sometimes does the right thing, but almost always for the wrong reasons. Is Jaime finally going to kill Cersei on Game of Thrones? The Kingslayer left his sister in the finale and may already be plotting her downfall.
While it may come to that, it's also still possible that Jaime is protecting his sister and her interests after having left her. Cersei is allegedly pregnant with his child, after all. As gratifying as it is to see Jaime finally break free of his sister's control, it may not be that easy. He doesn't believe that she would ever kill him, and the same may be true for him as well. This is not going to be an easy breakup for Jaime Lannister. It might take a while for him to work up to murder. Walking away from his sister was only the first step.
Jaime also covered his hand with a glove, the better to hide his identity, which indicates that he is not bound for King's Landing any time soon. Not only is Jaime Lannister diving right into enemy territory in pursuit of a nobler path as he joins the fight in the north, but he's doing it totally alone. He didn't even bring Bronn with him.
And, even if Jaime is harboring murderous thoughts about Cersei that would have fans cheering, the Night King and his army of the dead take priority. But, as for Season 8, what may happen is that Cersei will do something reckless with the Lannister army in retaliation for Jaime's betrayal, and that will spur twin to take down twin once and for all.
But, the saddest theory of all is that Arya will kill Cersei as Jaime, wearing his face. It would be satisfying to see the Stark assassin get to cross the biggest name off of her list while giving fans the visual closure of seeing Jaime kill Cersei. There's just the small problem that Jaime Lannister would have to be dead for Arya to do such a thing. After all that Jaime has been through, that would be a bummer. If he is going to kill Cersei, he should be able to be himself.