Kara no Naka no Kotori 4

Fallen revolutionary Foster finds refuge with railroad tycoon Dred Burton, who ties their pasts together in mysterious ways. Tasked with training elite courtesans, Foster molds each girl—clumsy Leese, eager Aya, innocent Ren, and poised Clair—into refined pleasures, their submission both duty and desire. Amidst nightly intimacy and whispered confessions, Foster struggles to reconcile his lost love with the growing devotion of these women, all bound to Dred’s enigmatic will through passion and servitude.