Kiss From the Cursed Prince

Skylar, a seemingly powerless princess, flees her jealous queen stepmother and meets cursed prince Lucian in the forest. He turns dwarf by day and burns in fire at night. After falling in love, they fight the queen and his vengeful fiancée. When Skylar sacrifices herself for him, his curse breaks, and her hidden world-controlling power awakens to defeat the thunder clan, ending with their wedding.