Thor's smile widens at Tony's reaction. The ring is still in his hand, pressed tight enough against his palm that he's sure there'll be a little circle-shaped indent inside of it by the time all of this is over.

"Tony Stark. Billionaire. Inventor. Playboy. Philanthropist. Prince of Asgard. The title and all its privileges are there if you want it. Prince Anthony does have a ring to it."