Sara became a sex slave to her clingy department chief after covering up her boyfriend's minor mistakes at work. This big-breasted office lady, who finds her superior repulsive on a physical level, is gradually brainwashed through NTR (cuckold) humiliation and falls into depravity. She undergoes lewd training sessions relentlessly, even during work hours. Her boyfriend merely watches helplessly, making no attempt to save her—instead, he gets turned on by her degradation. The presence of this trash boyfriend, aroused by her suffering, deepens the story's intensity.