Eustia Astraea

The title character, Eustia (everyone calls her Tia for short) was saved from having to work as a prostitute after Caim buys her. An orphan for as long as she could remember, Tia grew up under harsh conditions, having worked as a slave for a noble family before ending up in the “Prison”.

Spoiler

She is found to have the wing disease, although her wings are markedly different from the others; it is quickly revealed that Tia is a special winged case and may possess supernatural powers.

She is cheerful and optimistic, and she believes that there is a greater purpose to her life from the periodic dreams she sees. She is driven by a huge desire to help and bring happiness to others, especially Caim, whom she looks up to as the one who changed her bitter life up to that point for the better.