ahem ahem ahem:
Two neighboring kingdoms have been at war for many years, their rulers in a bitter feud with each other. Do I think these kingdoms have polar opposite fuckin' gorgeous aesthetics? Yes. Do I think one is dark royalty while the others more light? Yes.
After many years, the dark aesthetic kingdom has declared that it wants a truce with the light aesthetic kingdom, cemented through the marriage of the dark kingdom's prince and the light kingdom's princess.
BUT HERE'S THE TWIST:
It's a fuckin' trap. The prince has in fact been sent to kill the princess in a case of espionage, weakening the opposing kingdom by killing of it's only heir and giving his kingdom the opportunity to swoop in and finish them off.
BUT-the prince ends up falling for the princess.