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, greeted me alone. 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 her brother was on a business trip, so it was just me and my big-breasted sister-in-law in this house.