Ethnically Korean with wide set dark eyes and dark wavy hair often dyed, usually blonde thanks to her brother, Jungwon's rebellious influence, who has purple hair. She is quite tall for her age (148cm) and very slender, due to family pressures on image.

As a pureblood child raised to be one of the member of the higher echelons of society, she has polished manners and charm, a deep understanding of how to read and manipulate other people and elegance to her every movement. Raised in a very lonely environment with only elder siblings, she is aloof and distrustful, slow to build friendships. She also is very self conscious and focused on presenting a perfect image of herself. She prefers her books, though not the library and seeks out quiet places to be alone.

However, she is not arrogant or prejudiced, learning of the wider world with exposure from her brother. She likes to keep her thoughts to herself, with a deep inner world of imagination, particularly enjoying old literature.

Her paternal grandfather is the head of the Gwangsan Kim clan, a socially important family in Korea, like the Malfoys or Blacks in Wizarding Britain. (Reflecting Muggle Korea's society, there are different clans bearing various surnames of different areas. This has special importance in Wizarding Korea (no South or North, which is often a culture shock to Muggleborns) which is a strongly pureblood led society.)

Subsequently, she grew with heavy societal pressure. As the youngest of four, Wonhee is prone to most rebellion and ignored by both parents. She was raised by servants and schooled privately by tutors at the Kim residence in Britain, an old refurbished wizarding estate in Glencoe, which she has resided in since she was 1 years old Her greatest idol is her brother Jungwon.

Her two elder brothers, Joowon and Jungwon, 12 and 10 years older respectively, graduated from Ilvermony. Joowon is in politics, following the footsteps of their grandfather and father. Jungwon is a dragonologist at the Imperial Dragon Reserve in Northern China, an Asian dragon sanctuary. Her elder sister, Sohee, 5 years older, attends Beauxbatons, being raised in France by maternal relatives.

Jungwon, being friends with several Muggleborns at his work, does not agree with the pureblood rhetoric of their family and hence influences Wonhee. Once a year, he takes her on trips around Europe and Asia, visiting both Muggle and magical places.

Wonhee is eligible for attendance to Hogwarts as she moved to Scotland when one years old when her father became Ambassador to Wizarding Britain and a member of the International Confederation of Wizards. So, her first accidental magic occured in her home in Scotland, at age 2, when her robes turned purple after her parents refused to allow her to wear purple, which upset her greatly. Her parents were immensely pleased when her robes went from dark blue to purple, as Squibs are deplored as family disgraces in most pureblood circles. Since childhood, purple has been her favourite colour.