Daenerys makes Grey Worm her Master of War after their siege on King's Landing at the very start of the finale, and almost immediately after, she's murdered by Jon Snow. Well, lucky for Daenerys, there's someone still very much committed to upholding her legacy: Grey Worm. The Unsullied warrior kills all remaining Lannister soldiers on sight despite their surrender and imprisons Tyrion and Jon without a second thought (and passionately argues for Jon's death).
But, wait a second — if he is so dead-set on killing Jon for what he did to Daenerys, why would he ever be OK with Tyrion's "compromise" of sending Jon to the Wall? He does a complete 180 from wanting to execute both traitors — Jon and Tyrion — to willingly going along with the plan to elevate one of them to Hand of the King, allowing the other to go free, and then voting to allow one of the traitors' brother to become king.
I understand that Grey Worm doesn't have a lot of power in deciding either of their fates, but it seems odd how easily he capitulates to the council's decree. Perhaps, like seemingly everything else in this season, we're just supposed to assume that his complaints were made off screen.
