As the princess and the only heir of the Kouka Kingdom, Yona was raised with extreme care and gets whatever she wants, for example, beautiful accessories and clothing. This leads her to being a spoiled princess. After some life-changing events, Yona developed into a strong young lady who lives for the people of Kouka Kingdom, while also paying back the friends who helped her survive.

Although the daughter of a respectable family, she's a martial arts-loving junior high-school student. After being saved by Yato, she becomes more prone to having out-of-body experiences. She has an older brother. She also has a pink tail emerging from her body whenever she falls asleep.