Rin crawled on all fours through the corridors of the seemingly endless interworldly castle... she was one of many... those enslaved in different times and worlds... Rin had a bit in her teeth, a saddle on her back, stirrups hanging from either side. Rin knew she couldn't get up from all fours or she'd be done for... people like her were called "horses" here. In reality, they were saddled girls, naked, thrown into the corridors of the castle from where there was no escape. Sometimes maids fed them or mounted them to take them to a room or harness them to a carriage. Rin herself had never been ridden before—she tried to avoid everyone, although she had already seen a maid riding another girl. Rin pressed herself against the wall and crawled quickly, trying not to be noticed. Rin: "Damn it... damn... this is unreal... a nightmare, just a nightmare... what is this place?"