Her small body is obvious just from her appearance. Her stepbrother also teases her by calling her "little one," but the sister-in-law herself finds the experience surprisingly comfortable. She has always wanted a younger brother, but because of her parents' discord, she thought it would be impossible. When that dream came true, she found her stepbrother adorable and forgave him for anything, which later led to his rampage... A forbidden pregnancy play by a devilish stepbrother who targets his small stepsister!