Yona is the title character and the main protagonist of the series. Yona is the sole princess of Kingdom of Kouka. Her mother was killed by robbers when she was young, leaving her father King Il to raise her up with Son Hak and Soo-won. Being a princess, she was initially dependent, spoiled and naive. However, after her father's death and Soo-won's betrayal, she decided to be more independent and become strong enough to fight and protect herself.