Name: Tsukasa Taira
Species: Human
Gender: Female
Age: 22-23
Height: 5'0"
Hair Color: Light brown
Eye Color: Brown
Date of Birth: March 21st, 1991
Unique Features: A scar across her nose and onto the right half of her face.

Tsukasa is the female protagonist of the Devils' Line series.
She is a first-year graduate student at Keio University, where she originally studied Humanities and Geography.
She is a kind-hearted human who falls in love with Yuuki Anzai at almost first sight.
Despite the difficulties of being in a devil/human relationship, she stays positive and is always trying to make it work. She is strong willed, determined and stubborn at times, as well.
She cares about Anzai and his suffering as a half-devil very much, and is constantly looking for something she can do to help him.
After becoming more aware of the devils' situation in society and learning more about them, she is thinking about researching the devils, or rather study sociology and about devil problems, as she claims that devil problems are human problems as well.

(Source: Devils Line Wiki)

As of chapter 49-50 of the manga:
She is learning self-diffidence.
As of chapter 52 of the manga:
She is trying to find ways to SAFELY (without being killed in the process) be intimate with Yuuki. Going so far as to restrain him in a special bed (with his consent/at his request), muzzle him and have a doctor in another room able to watch them, in case he loses control and turns into a violent monster, during the act.