Lilly Satou is one of the five main female characters of Katawa Shoujo. She often speaks in a very well-bred and formal manner, even to those she is close with. She is completely blind in both eyes, however, she never likes being pitied by anyone else in spite of her lack of vision, and as such has grown up strong-willed and independent. She enjoys being seen as someone who people can look up to, and acts very motherly to many people around her, be it Hanako, Hisao, or the members of her class.

She is half Scottish (on her mother's side) and half Japanese (on her father's side). As such, she has extended family in Scotland, and was taught English at a very young age.