Since childhood, Hayu has never won against Yuki-chan, her genius of a neighbor and childhood friend. But when Yuki-chan moved, Hayu could finally content herself in being number one in everything. But after 10 years, Yuki-chan moved back. With his newfound good looks to go along with his brain, he attracts a fascination that threatens to topple Hayu from her position. But behind his angelic face lies a demonic attitude that he lets only Hayu see.