Yousuke Toyokawa
The main character of the story. He spent the last several years trying to locate his beloved sister, until he found her (sort of). The biggest clues he has when questioned about his sister's identity is a charm necklace he gave her and a drawing she made with her name on it. Ayu and Mayu both remember having a brother, but they can't remember their brothers appearance. And half the name was torn off the drawing. As the story progresses, he finds himself liking both Ayu and Mayu, wishing they both were his younger sisters.
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