Yuu was my brother's classmate and my senior in school. Unlike my brother, Yuu was kind to me, who was shy and dull, and I've always had a one-sided admiration for her... But I never thought I'd marry my brother... I'm staying with my brother and his wife while I'm looking for a job, but I have mixed feelings. Ever since she saw the letter I wrote to Yuu san back then, which I never gave to her and kept instead of throwing it away, I've had creampie sex with Yuu many times...