SPOILERS AHEAD, READ AT YOUR OWN DISCRETION!
If you haven't played Mystic Messenger completely, you might read something that will reveal to you the complete story of the game. So please pay attention!
Sarah Choi is a side character who is involved in the majority of Jumin Han's route, and can be considered as one of the two antagonists in the events of his route; the other being Glam Choi (Sarah's sister).
In Jumin's route, Chairman Han (Jumin's father) declares that his intentions to marry Glam and expresses wishes to make Sarah his son's fiancé.
Personality
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 as she calls herself Jumin Han's fiancée.
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.
Appearance
Sarah is shown as a relatively slender fair-skinned woman with long, magenta hair, light brown eyes and an hourglass figure. She is shown wearing blue earrings with a matching blue necklace, a long sleeved purple 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 Glam Choi (Sarah's sister). Her appearance beforehand is unknown.
Role
Glam Choi planned for Sarah 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.
Background
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.
Relationships
Jumin Han
Sarah was supposed to marry Jumin, but the two never really got along very well.
Chairman Han
Glam Choi
Glam is Sarah's sister.
Elizabeth 3rd
Sarah doesn't like Elizabeth and she has questioned why Jumin bothers with a cat, because she gets fur everywhere.
Trivia
- The name Sarah means "lady, princess, noblewoman" in Hebrew.
- Sarah believes Jaehee Kang looks average.
- Despite Sarah surname being the same as 707's and Unknown's, it is reasonable to assume they are not related as Choi is a common surname in South Korea.