In Jumin's route, his father, Chairman Han, declares his intentions to marry Glam Choi, and expresses wishes to make Sarah his son's fiancée.
Not much is known about Sarah's true personality other than her greed when it comes to money. She seems to be very loyal to her sister, Glam Choi, and is willing to go through tedious tasks to get what she wants. Sarah doesn't seem to be afraid of flaunting her looks and position, calling herself Jumin's fiancee.
However, she becomes extremely defensive when her reputation is on the line, to the point of threatening to sue those who write bad things about her.
She portrays herself as an upbeat woman, very cheerful and caring. When talking to those other than her sister, she displays a fake persona. She seemingly pretends to act hurt and defeated when her advances on Jumin don't work, though sometimes making joking remarks at how cold he is towards her.
Sarah is shown as a relatively slender woman with that of an hourglass figure. She has long, magenta coloured hair with light brown eyes and fair skin. She is shown wearing blue earrings with a matching blue necklace, a long sleeved purple coloured shirt with brown pants, and a bag.
It is stated that she had undergone extreme plastic surgery to the point where she doesn't look similar to her sister, Glam Choi. Her appearance beforehand is unknown.
Not much is known about Sarah's history. All that is stated is that at some point both her and Glam Choi were wealthy then lost their wealth, causing Sarah to undergo extreme plastic surgery and creating the food company Sugar Round so that they can marry into wealth, have them buy the company from them, then eventually leaving them with the money.
Glam Choi planned for her to marry Jumin Han. After the failure of her company "Sugar Round" she received plastic surgery and a fake ID to approach Jumin's father on an arranged marriage. Once married she wanted to sell her company at a large price knowing that Chairman Han of C&R would purchase it, which would, in turn, solve their financial issues.
She was supposed to marry him, but the two never really got along very well.
Sarah doesn't like her and has questioned why Jumin bothers with a cat, because she gets fur everywhere.