Asuna Okai
Birthday: 5/14/1996
Gender: Female
Place Of Birth: Tokorozawa, Saitama, Japan

岡井明日菜 (Okai Asuna), legal name 矢島明日菜 (Yajima Asuna), is a former member of the Hello! Project trainee group Hello Pro Egg. She is the younger sister of ℃-ute's Okai Chisato.