Nina has been married for a while but the couple still does not have children. Her in-laws constantly urge her, making Nina feel extremely pressured. On the occasion of an upcoming family trip to a hot spring, her mother-in-law requests Nina to restrain her sexual desire for a month before the trip. Releasing the suppressed sexual desire for a month at the hot spring will help Nina conceive more easily. The day of departure has arrived, and the whole family sets off together. When they arrive, because she has restrained herself for so long, Nina is craving for sex. But Nina's husband ignores this, leaving her to masturbate to relieve her desire. Nina's father-in-law also wants to have sex with her but she refuses. Passing by Nina's bathroom, he sees her masturbating, and realizes Nina's current situation. After dinner, Nina continues to masturbate. This time, her father-in-law cannot resist anymore, he enters and has sex with her! Nina resists weakly, but quickly succumbs to the pleasure and desire that her father-in-law brings. Nina takes the initiative to tease and rides her father-in-law's bare, hard cock, letting him ejaculate inside her womb. During their stay, the two secretly have sex with each other repeatedly, even though Nina's husband is sleeping next to her. After some time back home, Nina discovers she is pregnant. Her husband and mother-in-law are extremely happy, only Nina and her father-in-law feel extremely awkward, as both know who the child in her womb belongs to...