Azu lives a boring life in her hometown. She is interested in erotic things and is tormented by information and videos on the internet. One day, when Azu comes home, her sister and her husband have come back to visit for the first time in a long time, and the house is bustling. That evening, after a party, Azu sees her sister's husband's cock, who is drunk. She is intrigued by her brother-in-law's cock, which is a good size even though it is not erect! After that, Azu's mind is filled with thoughts of her brother-in-law's cock, and she finally sneaks into the room where her sister and her husband are sleeping...