PGD-813 I believe in my sister-in-law. Kawakami Yuu.

My respected older brother and the woman I admire like a real sister, my sister-in-law Yuu-san. Although it was only for a short period, I lived happily with the two of them. But something seems off about my sister-in-law. Suspicious visitors, gestures as if hiding something... There's no way she would cheat. To protect the peace in this house, I decided to take action. I believe in my sister-in-law... New Sister-in-Law Stealing Drama Series Episode 1!