Dan Oniroku's Rondo of Flesh(2007)

Three years ago, when Eriko was a new office worker, her boss, Adachi, had been trying every trick in the book to get closer to her. The two were having an affair, and Eriko, who had given him her virginity and got pregnant, had been giving in to his sexually harassing demands as he wanted to have everything to himself, and she had been trusting and waiting for Adachi. However, six months later, Adachi, who had stolen Eriko's project and been promoted from section chief to department head, unilaterally broke up with her. Stunned, Eriko drank heavily. On her way home, she passed out drunk on the side of the road and was kidnapped by unknown men. When she came to, she found herself in a deserted building. Koji and Saburo kidnapped Eriko, bound her with rough rope, and repeatedly raped her. Eriko could not refuse Koji and Saburo's persistent advances. As their encounters continued, Eriko began to enjoy the feel of the ropes against her skin...