There's little to say that'd surprise you about the standard, under-pressure temperament of a charizard: aggressive, brash, and controlling. Despite being fairly collected most of the time, Charkol is one to frequently delve into those traits when things aren't going his way or he feels as if he's being threatened. Despite having claws and a flame at his disposal, Charkol knows quite well that the display of a gun and it's cold touch to someone's head is a pretty easy way to present a choice to either cooperate or be left with a hole in their skull.
Nogard here seems to be debating which of the two to consider, even with Charkol giving his final ultimatum. Of course, second chances are rarely given when under stress like this, so the pinned dragon better choose wisely.
The pose is inspired by executions from The Last of Us.