Touch by Touch

Seon-mi hands a name card to Joo-hee who is about to get married, saying that she'll be able to feel sexual satisfaction like never before. Joo-hee experiences something new and starts expressing her rising emotions to her fiance despite the time and place. Unlike Joo-hee who is enjoying this, Min-woo is getting tired. He tries to satisfy her to the best of his abilities and even asks for advice from friends but it's not enough. What is that place that has her upside down like this?