149cm tall sister Momoka grew up surrounded by tall, kind, and dependable older brothers. Having cherished her beloved "big brother who used to change her diapers" since childhood, she recently heard he's been depressed, lost his job, and seems down—prompting her to rush over and stay at his place. Driven solely by the desire to cheer him up, she begins touching his body and drawing close emotionally. Then, she exposes her pussy and starts stimulating his cock. Coming back to his senses, her brother gets angry. In that moment, the shifting emotions between them—will they inevitably lead to incest?