Yagami Shiina♀

Shiina is the daughter of Misako and her previous husband. She have moved in to Yuusuke's home together with Misako after her mother's new marriage. She is a kind step-sister and a pure girl who has never known mistrust. Because she has nobody to look up to as a fatherly figure in her life, she constantly seeks an older male who can act that role for her. Somewhat inevitably, she'll develop a girlish kind of crush on her new step-brother. Depending on Yuusuke's choices, their relationship could grow into something more than just that of a simple brother and sister.

[Edited from Geo's Walkthrough]