HMN-875 | A Room You Can't Leave Unless You Cum Inside: Four men and one woman are gathered together in a small space, locked in with the promise that their debts will be wiped out. Each time they ejaculate, the amount of debt they have to repay decreases, and they can leave the room. Because there's only one woman, she's repeatedly subjected to unprotected sex. (Rei Kuroshima)

Trapped in a small space furnished only with a bed are men and women who have been deemed unable to repay their debts. As a social experiment to combat the declining birthrate, the rule is that if they impregnate the woman, their debts will be wiped out. If they can get her pregnant and implant the egg, they can leave the room. The only woman is Rei, a desperate office worker who has spent all her money on hosts and is in debt to numerous consumer finance companies. In a space with only one woman, the only way to leave the room is inevitably to impregnate her. A morally bankrupt man rapes her, taking advantage of the situation. A cocky man wants to have sex with her but tries to protect her. A timid man is too guilty to do anything. A group orgy of impregnation and unprotected sex, where each person's despair, conflict, and sexual desires intertwine!