Sora is slim, has brown eyes and long burnette hair extending to the back that she keeps in two long pony tails at the back. She also appears to have cut bangs at the front of her face and a long strand of hair in the center.
Prior to the start of the series Sora was born and lived on Southern Cross Island, where she attended school. While she was in her second year of high school or even before, Sora and Ryousuke's parents arranged their engagement. Despite having deep feelings for Ryousuke, Sora felt as if he didn't feel the same way so she never pushed for anything deeper. One afternoon while looking at a rainbow from the beach with Ryousuke, they were approached by a young man by the name of Tokio Tsunashi who was a painter and wanted to paint the rainbow. Sora and Ryousuke soon became close friends with Tokio and eventually Sora fell in love with him. Tokio becam obsessed with painting Sora to the point where he painted many pictures of her without clothing. Eventually after Tokio had become more obsessed with obtaining a mark to achieve his own personal goals, he abandoned a pregnant Sora and only focused on Shingo. While talking to Ryousuke, Sora shows her jealousy towards Shingo and Ryousuke then talks about why their trio came to what it is, how Tokio's obsession has lead him to lose his love not only for painting but Sora as well and then reveals to Sora that he is aware of her pregnancy. Sora then gets upset at Ryousuke and says that he never cared for her, however Ryousuke the says that he did. Sora doesn't accept this and yells that he was lying however realizes that it's true when Ryousuke gives her his precious pocket watch and finds that inside it is a picture of her. After this Sora then leaves the island and leaves her child with Tokio's grandfather and is never heard from again.