A man with no memory of his past awakens as the Master of a lavish mansion, where he serves as a trainer of slaves under the direction of the enigmatic Lady Regina. After taking in a desperate woman named Lita, he subjects her to a rigorous and degrading training regimen to prepare her for a competition. However, as he suffers from mysterious headaches and fragmented visions, he begins to suspect that his identity is being intentionally suppressed by the mansion's residents through medication and manipulation.
As the high-stakes competition event nears, Lita endures grueling training and reveals glimpses of her traumatic past. After a mysterious disappearance and a subsequent assault, Lita is forced into a public display of extreme degradation for wealthy buyers. Amidst the cruelty, the Master reveals a chilling truth about Elza's disappearance and the fragmented memories of Kaoruko.