Whang Chung-Yoo/Hwang Dong-Young is the Princess of Heaven and the main protagonist of Angel diary. She eventually falls in love and marries her fiance the King of Hell, also becoming a female King of Heaven.
Whang Chung-Yoo, also known as Dong-Young is the youngest daughter of the Rulers of Heaven. She has an engagement with the King of Hell. She ran away, believing the King of Hell is a "perverted old man" who possibly is her father's age or a grandfather's age.
When on Earth and when her powers are sealed, she is Dong-Young, her alter-ego. She is disguised as a cute boy. "He" is often assumed to be gay, because of her appearance as a boy and being smothered by Jin Bi-Wal, the King of Hell. The King of Hell and the Princess are really close, so almost everybody who attends their school, believes they are homosexuals or "boy-lovers".
At the end of the series, it revealed that she married her fiancee and became the Supreme Lord of Heaven.
During the series, it revealed that all Whang Chun-Yoo ever wanted was to have a life of "freedom". She just wants to move away, get married, sitting on her butt all day, slowly inheriting money like her four elder brothers. (Whang Chun-Yoo's second brother was originally to become the next ruler of Heaven. He often tried to attempt suicide, even with the support of his siblings.)
When in her human form, she takes on the appearance of a boy. She cuts her hair short and prefers to be a boy because of her past childhood. In Heaven, all children born genderless until they reach a certain age when they pick a sex. Whang Chun-Yoo's first choice of gender was to be a boy (like her elder siblings), but for the treaty of Hell and Heaven, the youngest child of the King had to become a Princess. She hated the idea of being a girl for one, her hair grows back rapidly. (Even when cut short, her hair grows back within a week. Her hair grows at a normal human rate when her powers are sealed.) Another, when in disguse, she has to bind her chest as much as she can to be flat-chested.
In her celestial maiden form, she wears a traditional dress, her hair grows back within seconds to her ankles. When in her form, she can automatically summon the ice-snow sword. She has the General Winter's powers, but because of the engagement someone else is the General Winter.
Whang is skilled with the sword. She was taught how to by her instructor(s). She was a young boy then, she met her close friend, the White-Tiger, Ah-Hin.
Whang's ability is that if she has even the tiniest speck of a person's soul (blood), she is able to create a seed for them to be reborn. The seed can only work if they can be registered in Heaven or Hell if they are a human. If a demon, they must be reborn in a demon system area in order to sprout. She said the person's soul and body still exists, but their memories won't come back. They must start over as if they are a new person.
Another is that she can swap between her celestial maiden form when her powers are sealed, or human form at will when her powers are unsealed. (When she enters into earth).
Whang is skilled with the ice and snow sword, originally belonging to the General Winter. She inherited the sword because she was born with the General Winter's powers. She has powers involving ice and snow.
She seems to be skilled in martial arts. She also knows self-defense.
Whang's personality can be a bit unpreditable. She punches Bi-Wal in the torso whenever he gets to flirty with her. Many think that the princess is pretty stupid. She often takes a bit to realize what a mistake she has made. Her thinking often involves: not thinking ahead, not remembering somethings, and has a habit to speak to her brothers as a male would.
She has a tomboy attitude. It is because her childhood when she grew up to be a boy. Whang is a bit shy and can be overwhelmed by embarressement. When the Black Turtle and Bi-Wal caught Whang with her bound chest, she became very flustered. The Black Turtle had no idea that Doug-Young was a girl, though he still hadn't realized she is the princess. *Later he found out in the series. But Bi-Wal had known that Whang was a girl since before the start of the series.