Ruby is a beautiful girl with light skin and blonde hair, quite similar to her mother Ai. In her left eye she has a star similar to her mother's, which causes her to be compared to her. Her eyes are Ruby in color, and she usually seen in her school uniform or with different home outfits. She is the 2nd daughter of the idol Ai Hoshino, like her brother Aqua. She is 1.58 and have 17 years. She is someone caring, cheerful, social, kind and funny.