The key to charming your dragon in manhwa is through bravery and loyalty. Stand by its side in difficult times and prove your worth. Additionally, using special powers or gifts might help win its heart.
It could be through some kind of magical transformation or a hidden heritage revealed. Maybe there was a prophecy or a special event that triggered it.
Often, in such manhwas, the princess becomes the queen due to various factors. It could be because of her noble birthright, her ability to handle political intrigues, or her kindness and wisdom that win the hearts of the people and the support of important allies.