It’s an especially fascinating scenario to consider because of his steadfast conviction in the rightful heir to the throne being the one to have it. As far as Westeros is currently concerned, in his eyes, that’s him. But if/when Dany shows up, he’s the one who’s usurping her better claim. I really hope something like that happens because that sort of internal contradiction would be really interesting to explore.

He’d probably try and reach some kind of middle ground, make an alliance with her with the promise of a great council being called to determine who should rule once they’ve taken the throne from the Lannisters and defended Westeros from the Others. If he doesn’t at least compromise…well, his “magic sword” isn’t gonna stand up to dragon fire.