Long Time No Sex (Korean Drama)

Woo Jin and Samuel, a sexless married couple, are utterly fed up with their lives. To improve their circumstances, they choose to earn money by blackmailing unfaithful couples. As they track down these couples, they find financial stability and rediscover their own connection. They start working on their own issues, but the more they delve into it, the hidden truth resurfaces, complicating their journey. What is the truth that they have been avoiding?