My take on it is:
he's already desperate. The prince even mentions that he has what he calls "useless emotions" for her. He knows he's in love or falling, and he feels hurt that she is so adamant that she doesn't/ can't feel the same.
His way of trying to get it out of her (a love confession) was WRONG -pure way of the trash- but he isn't a white-haired womanizer who needs to get his heart broken, he's a heartbroken womanizer who needs to learn better ways to communicate and deal with his anger/frustration.
As for the duke I liked him until that stupid smirk of his. It gave me "I'm nailing your mark" vibes... That put him closer to the emotionally dumb prince in terms of maturity for me...
Oh, please don't misunderstand! I just used their hair color and the term best to describe them right now. I was actually gonna call him a white-haired dick. If the duke turns out to be a trash, then it actually fits, “black(-haired) trashbag”. But right now, he's an enigma since we don't know anything about him yet. (And I really like black hair, and long hair, on male characters, and mysterious/silent type of characters more than the proud and ambitious once)
Anyway, I already know that he's getting desperate. But I want to see him get more desperate than that, I know it's quite cruel or sadistic. This action of him actually, giving the fl the cold treatment before, is the pull method(?). Like if I act distant to you, even I don't really want to, you'll be more honest with your feelings. But the fl is too inexperienced in things like this and currently thinks that the prince didn't really give their “special moment” second thoughts.
And yes, I understand. I'm a masochist for angst too. The best feeling I felt is when my chest hurts, my thighs too...for some reason...? There's a manga that I constantly return to just to feel that.
Duke > Prince. Sorry, black-haired enigma over white-haired womanizer anytime, any place—I just hope the Duke is not some manipulative bastard...
The only reason I'm not dropping this is because I just want to see the face of the prince contorted with regret once he realized that he loves but he hurt Sahara, and her avoiding him and giving him the cold shoulder. Idk. It's just nice to see when the roles are reversed.
“Look who's desperate now.”—kind of thing.