The biggest plot point of this season was the two primary protagonists finally meeting. Jon Snow and Daenerys Targaryen came face to face after several years of fans speculating what would happen if they did. Sparks were flying between the two for all seven episodes.
Tyrion stood outside the door as his queen and the King in the North got it on. He had a very interesting look on his face as he realized what was going down in that room. What exactly was he thinking here?
The truth of the matter is that was a look of grave concern. Don't forget, he's dedicated his life to this woman. He feels she can make the world a better place. This course of action will likely only lead to disaster.
First of all, this is Game Of Thrones. When was the last time you remember a character falling in love and it ending up happily ever after? This is a complex political show, and there are consequences to every action.
For example, the Lords in the North were not happy about Jon going to meet with Daenerys in the first place. They're likely to be furious when they find out he's bent the knee on their behalf. When they find out they're sleeping together, that will only make things worse.
It'll also complicate his strained relationship with Sansa. She may stick up for him and offer herself as a buffer between him and the angry Northern Lords. But there's only so much she can do. Who can protect them if the North goes into rebellion over this alleged treason?
Not to mention, there's Cersei. She's the most ruthless character possibly in all of fiction. If she learns of this romance she'll see it as a weakness waiting to be exploited. I'm not looking forward to seeing how she can turn this into a tragedy.
I'll admit, there's no way Tyrion could have known about this...but those two are totally related. From a meta perspective, Tyrion is representing the audience in this scene. That's the look you make when you watch a guy bang his aunt.
Lastly, there are freaking zombies on the march. The last thing these two need is anything distracting them. The Great War is officially upon them. Tyrion knows how high the stakes are and can't advise this tryst being anything but a terrible idea.
Especially since the wall just came crashing down. That was the only thing separating the Wights and White Walkers from entering Westeros for over 8,000 years. The look on Tyrion's face may have been a bit ambiguous, but this closing shot wasn't. With only six episodes remaining in the series, season eight is going to be nuts...when it comes out in 2019.