@Kampfarsch It was a childhood crush that was never able to properly blossom, but since he's engaged to her there's no way he won't be able to meet her again and thus looks forward to it. He wants to get to know her better, and because he doesn't have anything else to base her off other than when they met as children and any potential rumors his attraction was thus left to his imagination. 12 years of imagining his fiance as a bubbly, friendly, clumsy, and cute girl who
treats him normally rather than as "The Crown Prince," and of course he'd be hung up on her. Wanting to "repair" his relationship with her(that, admittedly, he indeed never had) is a good sign. It means he wants to talk with her properly and develop a proper relationship with her, but because he never gets to see her he can't.
You can think it creepy if you'd like, that's your choice. But I personally don't think it's creepy in the slightest nor do I think it
should be viewed as such. Just puppy love that hasn't had the chance to mature.