My older brother's wife appears gentle and kind on the outside, with a calm and sweet personality, but she has a surprisingly erotic side. While I'm sleeping in my room, she sneaks in, pulls down my pants, and gives me blowjobs. She knows I'm watching and deliberately shows off her sexy body, even letting me catch glimpses of her bathing. This went on day after day—until one day, my brother had to go on a temporary business trip, leaving me alone at home with my sister-in-law for the first time.