As a snake, she was never taken care of and had to live on her own. She was feared by all, and the only one that had ever accepted her was a young human, but they eventually left too. She wished to be like everyone else, but instead gained the ability to take on a humanlike form. Even in this form, however, she was rejected and left alone once again.
Dark, Moody, Likes to pick on protagonist, Can be sassy, Sharp-tongued Link to the script
Just going through some short descriptions of her.
Hair: Violet with black highlights, shoulder length
Skin tone: Pale
Clothes: Baggy but not schlumpy
Summary: Snakes grow up fending for themselves from the day they are born, so she never had a problem with that kind of lifestyle. However, she was feared by any and all creatures she tried to interact with, despite the fact that she only ever hunted to survive and has a kind soul. During the previous meteor shower, she touched a meteorite with the hope of being accepted like everyone else. She gained the ability to take on a humanlike form, but this form still remained snakelike in appearance, ostracizing her from both humans and animals alike. Because of this she has grown cold, and due to the fact that her wish was never granted properly, she could not continue aging until it was (Note: she only speculates this. There are many mysteries surrounding the magic in most of the routes).
Human Arc (Only unlocked after seeing the Part 2 good ends for all the girls)
School has begun, and somehow you've managed to fill out all the paperwork so that she can enroll at school with you. The two of you are now living together since she has nowhere to stay.
She still likes to pick on you, which allows her to quickly develop a friendship with Yuuji (because he also teases you). Ami greatly dislikes her because she thinks you deserve to be treated better, even though you know it's all said mostly in jest. Out of all the girls, she and Ami have the most outspoken dislike for one another.