ピアノ ～紅楼館の隷嬢達～

Takajou Takumi lost his parents in an accident. The only relative he has in his life is his precious sister, Miu. He and she were placed into a mansion run by their Chinese uncle. There, they meet various girls in refuge, to what they thought they call a "garden."

His uncle designates Takumi to become the successor of the mansion. He has been trying to make him the successor against his own wishes only because his father was a slave trainer. His father has trained many women into becoming successful sex slaves during his days. That bloodline is now passed to Takumi and he is expected to follow in his footsteps or else...