This work compiles videos originally featured in the SM magazine "Mania Club." The protagonist, Keiko, is a woman who has vowed to serve as a sex slave and masochist for her master, Yodo Chikushi (pseudonym), until the end of her life. A genuine masochist, she has engaged in self-bondage and masturbation since childhood, and was trained by Chikushi, whom she met by chance during university. After graduation, while working in elder care, she has spent nearly all her time in a livestock shed, being conditioned into a dedicated sex slave. On days when her master is absent, she follows strict routines: vaginal contraction exercises, lip training for blowjobs, filming self-masturbation videos, crafting perverted handmade outfits, and writing erotic fiction and illustrations—all aimed at sexual service to her master. This video was shot by her owner, Yodo Chikushi, at the request of the editorial department. It features a wide range of acts, including piston-style spanking on a fixed dummy chair, blowjob training on a dummy mounted on a mirror, simulated foursomes through master-inflicted violence, academic-style rope bondage techniques, dual-penetration teasing in BDSM attire, loaned-out training sessions with anilingus service, foot-licking service combined with buttock-dancing, serving as a fully naked inn maid with an anal hook attached, and semen swallowing. Notably, unlike Chika, another slave under the same master, Keiko has not undergone bodily modification—her slender, petite frame is preserved specifically for sexual service. She is trained to arouse men and extract semen using refined sexual techniques, functioning purely as a sex slave. Initially trained to service with her mouth, vagina, and anus, her anal sex was later prohibited to differentiate her from Chika. Currently, she is only permitted limited anal stimulation using fingers or vibrators. For her 40th birthday, she was forced to offer her anal "second virginity," enduring an extremely harsh session where her anus was used until ejaculation despite suffering lacerations.