After Sun-Young misses a proposal deadline and gets Ho-Jun reprimanded by his superior, he takes punishment into his own hands. During overtime, he spanks her and orders her to wear a vibrator for a full day.
Sun-Young asks her superior Ho-Jun to train her in a Master-Slave BDSM dynamic. His first command is for her to wear a vibrator while walking around. His second command is for her to perform oral sex on him under a table. She keeps his ejaculate in her mouth for the remainder of the workday, which immensely satisfies him. He then rushes her home for an intense sexual encounter.
Mrs. Lee So-hee feels very uncomfortable after running into some unknown man who seems to know about So-mi. So, Do-hoon comforts her with some hot sex. Do-hoon interrogates So-hee during sex, and after a few spankings and hair pulls, he figures out the identity of the unknown man, and it turns out that he's the father of Mrs. So-hee's kids.
Do-hoon makes Ye-eun attend the shoot afterparty where she drinks too much and gets drunk and dozes off. She awakens all tied up to Do-hoon who's about to torment her and make her submit to him by violating her asshole.