As children, Hazuki Nanase and the starry sky were childhood friends. When they were little, they always played together, hiding behind the curtains. Before they knew it, they had become a lesbian couple and stayed together. Then, Kaname Ruka transfers to their school. Nanase is instantly smitten with Ruka the moment she sees her and forcefully kisses her. This is accidentally witnessed by someone else. Jealousy and love. The subtle relationship among the three leads to what answer...?