I was laid off by my company and ended up staying at my brother's house for a while. When I got home, my brother was nowhere to be found, and my sister-in-law, Reika, came to greet me by herself. 'Reika', who is always bright and kind, is a big-breasted beauty who would be a shame for her older brother. She has secretly admired her since the first time they met. When I heard her story, it seemed like my brother was on a business trip, so it was just me and my big-breasted sister-in-law in this house... My heart was pounding when I thought about it. I wonder if Reika-san knows how I feel, but suddenly she starts taking baths and showing up in revealing clothes, and I'm so preoccupied with my brother's wife's big breasts that I can't even focus on job hunting. Oops.