Sayaka takes a part-time job at the Twin Wings Family Restaurant, only to discover that the establishment specializes in "training" its waitresses to provide provocative services to customers. Coerced by the restaurant's manager—who is also her boyfriend's brother—Sayaka is forced into a series of intimate and degrading acts. Despite her initial resistance and the guilt of betraying her partner, she gradually succumbs to the manager's relentless training and the forbidden pleasure it brings.