Aoi and Yuu are usually just normal siblings who get along well... but they have a secret. Once they were tempted and had sex, they had great chemistry, and the moment they were alone together, they became a brother and sister who would have sex instantly! Even after a friendly chat with their parents at a family get-together, they had sex as soon as they were alone! They have such good chemistry that once they get going, they can't stop! Their over-the-top sex is always full throttle!