When they were young, Min-joo and Seo-yeon cared for each other and were closer than brothers and sisters. However, she accidentally learns about Seo-yeon's tutor, Woo-hyeon, and because of this man, their 10-year friendship starts to become shaky. Meanwhile, Jeong-soo is hurt in seeing Min-joo like that, and so he distanced himself from Min-joo. Because of Min-joo and Seo-yeon's misunderstanding, Jeong-soo who couldn't care much might just leave so Min-joo tries to break up with the help of Seo-yeon. While in the process of breaking up, Min-joo and Seo-yeon went back to their close relationship. The love of women who have been separated because of man, and the two men's friendship is comically drawn.

At first, Yoo-jeong and Min-soo really loved each other. However, in a few months, there is a period of boredom between the two. Two people face each other and don't eat. Yoo-jeong confides her worries to her friend So-hyeon. But So-hyeon never misses the chance and confesses her feelings to Min-soo. Min-soo’s heart is shaken by So-hyeon. I'm meeting So-hyeon secretly. After a secret meeting with So-hyeon, he finds some time to relax.

Min Jung's husband has been traveling for 300 days and she feels lonely. When her friend Chung Hee moves in next door, Min Jung often visits her house, during which she keeps meeting Jae Ho, Jung Hee's son. After having an impulsive affair with Jae Ho, Min Jung tries to forget about it, saying, "It was a mistake," but she keeps remembering his young body.

Seo-yeon is being tutored by Woo-hyeon who is younger than her. She grew interested in her tutor, Woo-hyun, the first time she met him, and he is also fond of Seo-yeon. Seo-yeon succeeded in seducing Woo-hyeon with the help of her friend Min-joo. Even if Min-joo is aware of what Seo-yeon feels, she approaches Woo-hyeon. Seo-yeon gets mad at her best friend when she met Woo-hyeon. Min-joo, aware of the fact that it's her faultis also angered by Seo-yeon's appearance and tells her to meet Jeong-soo, her friend. Seo-yeon is also angry and tells Min-joo that she have to meet Jeong-soo as well. A bittersweet story about a man who is a very close friend is just about to start.

A young man is preparing for the public official exams and is invited to his aunt's house to stay to save money. There he encounters an unexpected attraction.

A young mother-in-law falls in love with her daughter's boyfriend.

Newly-moved Yoo-jeong had a housewarming party. So-hyeon and Min-soo gather their friends at the housewarming party and meet for the first time. Yoo-jeong falls asleep alone, and Min-soo secretly kisses Yoo-jeong. So-hyeon, who finds out, threatens Min-soo and plays with him. Min-soo had no choice but to accept So-hyeon's terms. Yoo-jeong misunderstands them. But in the process, Yoo-jeong herself finds herself interested in Min-soo. Recognizing that, So-hyeon gives up the room he originally intended to live in to Min-soo and leaves.

Mi-yeong, who lives in the backhouse comes between the strong friendship of Deuk-chan and Cheol-soo. Mi-yeong is usually blunt and cold, but in bed, it's a different story. Deuk-chan approaches her with love, but Cheol-soo only wants to remain sex partners with her. Meanwhile, Deuk-chan who loves Mi-yeong had an old sex partner, Hee-jin. Cheol-soo shows interest in Hee-jin. The love story of two youthful men and women begins...

Ga-yeon comes to Min-jae's house where he lives alone, and decides to live there. Min-jae is curious about Ga-yeon who he haven't seen in a long time. One day, Geon-soo goes to Min-jae's house to pick up some stuff and meets Ga-yeon. Ga-yeon seduces him. Min-jae finds out about it when he phoned Geon-soo. Da-hae meets Min-jae to become sex partners and frequently contacts each other. Min-jae gets angry at the sight of Geon-soo wearing only underwear at his house. Gayeon comes out to meet her friend Da-hae after a long time. Ga-yeon and Da-hae who were drinking, join after seeing Min-jae and Geon-soo. That night, Min-jae gets drunk and had sex with Ga-yeon and finds out that Da-hae is not in a relationship with Min-jae. The next day, Ga-yeon knows the relationship between Da-hae and Gun-soo, and she brings the four people together...

So-yeon is on a weekend date with her boyfriend, Ji-seok, and then she invites him to her house to save money on the motel. Her step brother, Sang-woo, comes home earlier than expected and sees them having sex. He records them secretly and plans to blackbail So-yeon with it.

Private secret of Na-yeon and Min-woo, the teacher who teaches herself from old times! As Min-woo's grades go up a lot, Na-yeon invites him to her house for a special class. Usually, she is a calm teacher, but her personality changes whenever she touches her body. Meanwhile, Na-yeon had another student named Jae-hyeon, who knows the relationship between Na-yeon and Min-woo and is jealous, but only enjoys the current situation. A special private tutoring class for two students and a female student, which is secretly conducted, is just beginning.

Da-hee and Min-soo, who seem to be a good couple, eat together and take a walk. They are always seen holding hands and taking a walk, so people envies them on the street. In fact, Da-hee had a husband. A mysterious man who comes after her husband goes to work... Da-hee's love story, who walks a dizzying tight rope between two men, is just unfolding.

Jun-ho and Min-soo, experience a hard time because of Da-hee who drinks whenever she breaks up with her boyfriend, but they still take care of her. But they heard that Da-hee is meeting her ex-boyfriend again. Actually, the two guys like Da-hee. They’re trying to make sure that Da-hee won't meet her boyfriend again. The love story between the two men, which is invisible to the eye, is just about to happen.

Da-hyun, the youngest of the three sisters, usually follows her brother-in-law well. When the youngest sister-in-law said that she found a boyfriend, brother-in-law Jun-seo congratulates her and prepares dinner. The next day, Da-hyun's boyfriend Jin-goo, goes to her house to thank her. Upon arriving, Jin-goo witnessed a shocking scene...

One day on the street, Mi-yeong greets Deuk-chan then he made a fuss, wondering if he likes Mi-yeong. Whenever he is having sex with Hee-jin, thoughts of Mi-yeong comes to him... Then one day, his friend Cheol-soo sets up a blind date. A few days later, the blind date happens and the woman who came is none other than Deuk-chan's dream, Mi-yeong. As soon as they meet, they go to the motel... Mi-yeong who is usually blunt looks so different in bed. Deuk-chan loved that Mi-yeong who finds eating harder than having sex. There's a subtle air between the two...

Seo-yeon likes Jin-woo, her friend since high school. She is satisfied with their current relationship where she hides her feelings and stay as a friend. Jin-woo is not greedy because he didn't have a girlfriend for a long time. Dong-hyeon, who secretly likes Seo-yeon, knows that Jin-woo and Seo-yeon like each other, but he doesn't say anything. As time went by, Dong-hyeon found out that Seo-yeon was unlikely to like him, and asked Seo-yeon to sleep with him because she will connect him to Jin-woo. The two men's mixed love between a woman is just beginning.

Jun-ho and Da-hee bumped into each other on the street. The two fell in love and confides with their friend Min-soo. Knowing that the two will miss each other, Min-soo spends his last sweet moment with Da-hee, his sex partner, and arranges a place for them to meet. The hot story of Da-hee's choice between two men who think that friendship is the most important, is just beginning.

Drunk Min-woo and Jae-hyeon attack Na-yeon's house. There, Jae-hyeon confirms that he likes Na-yeon. Min-woo secretly enjoys sex with Na-yeon, knowing that Jae-hyeon likes her. When she learns that he likes her, Na-yeon tries to use her heart... she is happy without knowing anything.

Having been happily married to Jae-hyun, Na-yeon accidentally learns about Jae-hyeon's wishes from her former sex partner Min-woo. Na-yeon, who is a little nervous after hearing Min-woo's words, confirms with Jae-hyeon and spends another night with Min-woo in anger. Min-woo, who had long been interested in Na-yeon, now begins to approach her as a real man, not as a sex partner, and she begins to open her heart little by little. The love story of two men surrounding a woman is just beginning.

Two men who love one woman. Every time, Seo-yeon chooses to have a relationship between two men every time. Jin-woo and Dong-hyeon compete while waiting on Seo-yeon. She doesn't think the relationship is strange. In fact, there is a reason for making unwanted choices between the two... who will be the last man who will win Seo-yeon's love. The never-ending love story of young men and woman is just beginning.