Hikari is a young woman that, at the start of the game suffers from extreme depression and self-esteem issues due to her bad past, where she would often be a target of emotional abuse or manipulation due to not thinking or acting in the same way as others around her, complete with a lack of social skills that prevent her from getting her message clear. 

Voice Reference: There is no official english voice for Hikari, so just go for a timid young sounding voice!