Kei Yoshikawa collapses at fifteen and leaves the hospital with a diagnosis that undoes the rest of his life: he is genetically female, and the body he grew up in was the anomaly. A year of treatment later he returns to the same high school as Megumi, a girl whose resemblance to the missing honor student Kei Yoshikawa nobody can stop remarking on. Her friend Makoto, one of the few people who know what happened, keeps the rumors at bay while the school's most powerful clique decides it wants Megumi for itself.