The fourth installment in the Livestock Female College Student Keiko series, this title presents a detailed record of the ongoing harsh training endured by the lowest-tier masochistic livestock girl Keiko under the control of Hiroto Tsukushi (pseudonym). From summer 2015 to autumn 2016, Keiko is subjected to extreme conditioning as she descends further into complete livestock status. At times, she is used as a flesh vessel for other men or forced to serve even lower-ranked female slaves, treated as the lowest of the low. Amid intense suffering and humiliation, she reaches her most intense pleasures, revealing her deeply depraved nature. This release features diverse content including public blowjob performances under the gaze of audiences in a porn theater, sudden intrusions by unexpected visitors, scenes from daily life including window views and graffiti, a swap exchange at a hot spring inn, forced lesbian sex and forced cunnilingus, BDSM hotel sessions, displays of perverted climaxes, lesbian face-sitting, experiences on an orgasm chair, themes of sin and punishment, mixed-gender outdoor bath play, forced lesbian gangbangs with strapon daisy chains, sexual servitude, handcrafted livestock panties, natural defecation while wearing diapers, bondage and flogging, guided paths to climax, use of mechanical blowjob devices, anal ball stimulation leading to orgasm, livestock kissing, use of anoscopes and electric toys, neck blood flow restriction, livestock orgasms combined with rimming, ejaculation machine training, anal hooks and service drills, wax torture scenes featuring two livestock subjects, self-degrading shows, rented sex slaves, instructions on livestock usage methods, incidents at a happening bar, and crucifixion in various positions.