Shizuka, a young girl struggling with an ever-growing sexual appetite, finds her older brother Ryouhei to be a curious and willing confidant. Their intimate conversations quickly escalate into forbidden physical exploration as she brazenly initiates passionate encounters. Driven by budding awareness and raw need, Shizuka and Ryouhei share a tense, thrilling secret, completely surrendering to their irresistible and taboo desire for one another.