When high schooler Sayaka awoke one morning, she found an unexpected guestat the family kitchen table -- Kai, a cool, handsome, aloof, and so-calledfamily friend of Sayaka's father. His temporary stay in her household andattendance to Sayaka's school is more than she's bargained for. But what secretsdoes Kai hold? What are his true intentions for his sudden appearance intoSayaka's life? Where does he disappear to every night? And what's up with thatblack...