Thinking about it again I remember a plot where the protagonist or one of the love interest had to wear a mask because they were so beautiful people would pass out from seeing them. If that's the case with him(because she cries upon seeing him and looks starstruck), maybe he interpreted as...
With how powerful Finea is, wherever they discover it, do you think the monarchy won't want her? With how lovable she is and her power she's prime material for his future wife.