It's been three months since the sister moved into the home of her brother and her husband, who is the brother's brother-in-law and has lost his job. The brother has been paying her a small part-time wage as a housekeeper. Seeing his sister comfort the depressed brother-in-law, the brother begins to feel a strange sensation in his crotch. When the sister goes to clean the brother's room and pulls back the duvet, she notices his erect cock. One day, while drinking together, it's revealed that the brother is spending a significant amount of money on sex workers. "What!? You're paying that much? What a waste! Just give that money to me instead, lol!" the sister says. The brother is bewildered, but suggests a negotiation. "Hmm? If you're giving me money, why not?" With the sense of alcohol, they start checking their chemistry, and soon they find themselves unable to stop. While both are pragmatic about the arrangement, they cross the line and their relationship continues to escalate...