In the year 2030, with 80% of the population being male and sexual crimes on the rise, a prison conducts research to increase the number of women. In this facility, inmate Yui is forced to orally pleasure the warden and perform sexual acts in wide-legged cowgirl position to receive special treatment. She actively participates in experiments to develop a drug that increases female births, undergoing vibrator stimulation to collect her arousal fluid. She invades men's baths, performing handjob to collect semen, risking her body for the research. Under the condition of pregnancy leading to her release, she uses double blowjob techniques to arouse two middle-aged men, experiencing consecutive creampie sex twice, resulting in pregnancy.