Sarai Yuiko Valmont goes by her middle name "Yuiko" or "Yui" for short. 

She was born in England however her father is Russian/French and her mother was Japanese. 

Before Yuiko was born her father was married. His wife (Patricia) gave birth to a baby named Victoria. The child was diagnosed with leukemia and passed away at age 8. Patricia Valmont committed suicide a year later. 

During his grief Nicholai became an alcoholic and womanizer. He took special interest in a local flowershop employee and together they had a child (Yuiko). However, Michiru passed away during childbirth leaving Yuiko to be raised by her father. The deaths in their family as well as taking care of her father through the years has led Yuiko to have a desire to become a nurse or doctor in order to help others. 

Yuiko is a kind and caring person. She is always ready to lend a hand or help someone in need. 

She also has a darker and perverse side to her that she tries to keep a secret. She loves wearing sexy lingerie and considers herself to be very attractive, but not vainly. 

Yuiko's favorite clothing are those from the 1980-1990 era of the United States.