- Mi Youn's Story
Mi Youn, a housewife who has spent last seven years giving birth to a child and doing household chores, finds her life not that interesting these days. Though she has no big complaints about her husband and there is no specific problem to her marriage life, she feels as if something is missing. While making a beanpaste pot stew or having a chat with ladies next door, she can't help making a sigh when she all of a sudden thinks that she is getting old this way. She still wants to be a cool lady and believes it's just too early to give up everything...
Right at this moment, Mi Youn's first love Jung Woo show up! He is not a boorish student in shabby clothes that he used to be 8 years ago. He's now a cool romantist who knows how to deal with ladies.
After she meets him a couple of times, having a cup of tea and chatting, she somehow ends up in a hotel room with him. This is not what she wanted... Having imagined only romantic relationship, she's unbearably afraid. As she listens to Jung Woo's showering sounds, nervous and confused, she after all breaks out of the room, feeling too guilty. She rushes to the elevator, but she confronts one lady next door there. Unlike Mi Youn who's frightened, Ae Kyung swiftly pretends as if nothing's wrong. From then on, the tug of war between the two women begins. Although Ae Kyung is supposed to be the guilty one, it's Mi Young who's fretting.
Both fearful and guilty, Mi Young tries to end her relationship with Jung Woo, but what is troubling is the fact that he's an attractive man she wants to date and she doesn't want to lose. Ae Kyung, the lady next door, gives Mi Youn cheeky advice predicting what would exactly happen next between Mi Youn and Jung Woo. Ae Kyung tells Mi Youn to give him just 20% of herself and decide if she's going to have a couple of cups of tea with him or do something more than that. Mi Youn is just too afraid of and annoyed by Ae Kyung's pithy remarks. She's insulting my love that seems like the last beautiful one in my life, Mi Youn thinks.
Jung Woo is a true romantist who knows how to understand women and present sweet moments to them. Mi Youn slowly falls in love with him no matter how hard she tries not to do so. After her running several risks, there comes a moment when her love is nearly exposed to her husband. However, she narrowly avoids the crisis with the help of Ae Kyung, who tells her husband a lie that Mi Youn went with her to a grocery. Ae Kyung gives Mi Youn a hard time over her mistake, and scolds her that she should end the relationship and return to her normal life unless she wants to get divorced. However, she has come too far to return to where she was. Jung Woo is a sensible man who solves all of Mi Youn's problems as if he can read her mind. He praises her a lot, cheering up the housewife, tired of 8 years of marriage life, and tells her that before the age of 40, it's never late to start anything.
When Mi Youn a cosmetics company's recruitment ad saying , inspired by Jung Woo, she finds a job in the company as a BP. It's neither accounting nor computing. It's just cosmetics. I will show that I can do it, she thinks. Though she ambitiously goes to work for the first time in 8 years, she faces a formidable world. She is at last fired after buying cosmetics with her credit card to improve her performance... She lies to Jung Woo that she resigned to maintain her self-respect, but she grumbles and gripes about herself, weeping in her husband's arms. It's not just because of a sense of guilt or morality that she is resolved not to cross the red line with Jung Woo. Would it sound too grandiose if she says that it's because of an 8-year-old relationship with her husband, who is like a long time roommate or a much older big brother. She thinks that she should by all means avoid crossing the line, but that is harder than it sounds, and she narrowly shuns risky situations...

- Ae Kyung's Story
Ae Kyung is the perfect wife that every husband wants. She is beautiful, cute, a great cook, and a big earner. She takes the advantage of her great cooking skills, and opens a sandwich restaurant, which is even introduced on the Internet as a magnificent restaurant. Thanks to the fact that she's a superwoman both as a good wife at home and an able careerist at work, she's envied by ladies next door. Her husband is a gentleman who is a prestigious university graduate, and together with Ae Kyung, he makes the perfect couple. They get the spotlight when they enter tennis court near the apartment in white tennis suits. In short, they are the perfect couple.
However, Ae Kyung has long given up sexual satisfaction with her husband. He has avoided sexual relationship with her since he started business 3 years ago. It seems like he has impotent problems, but she can't talk about them for it may humiliate him. Not that she has ever thought of something troublesome like a divorce. Therefore, she fills the 20% that's missing outside her marriage life, and this vitalizes her a lot. There is no sense of guilt. This is my life, and I don't have that much left in my life. I'll just try to be an energetic and joyful wife, she thinks. The world's most flirtatious and unfaithful wife has several rules. Never date one guy for a long time. Don't be stupid to seriously fall in love with a man. Just give him 20% of myself... But, things start to go wrong since she comes across Mi Youn in the elevator of a hotel.
Mi Youn, just a novice, foolishly shows every sign that she's having an extramarital affair. Knowing what will happen if Mi Youn goes that way, Ae Kyung unintentionally gives several pieces of advice to her but she doesn't get them.
It's even more difficult for Ae Kyung to see Mi Youn dangerously enjoy her extramarital affairs. Ae Kyung even voluntarily defended Mi Youn when her husband nearly detected her affair. Ae Kyung tries to just ignore what's happening, but Mi Youn gets to know Ae Kyung's secret that even her husband doesn't know about. The secret is that she was a problem child, but had a couple of plastic operations, which made today's Ae Kyung. She doesn't even think about it! She becomes the past problem child for a short time when she confronts middle school gangs who annoy Soo Mi's twin sons and a notorious husband in the 14th floor who frequently beats up his wife.

Soo Mi's Story
Soo Mi is like a brave lioness who manages a beauty salon near the apartment. Once she gets angry, she shouts and yells, but she is by no means a narrow-minded person. She is the de facto head of the family with her small, timid husband, Bong Sup, playing the role of a housewife. Therefore, everything is the opposite in their house. When having a sexual relationship, Soo Mi loudly shouts "Let's do it!" and Bong Sup feels like hiding somewhere else, dejected. He even shudders when Soo Mi cooks him something good for his sexual vigor. Always suppressed by wife, Bong Sup encounters an unexpected romance. Eun Sook, a saleswoman at the vegetable section, is the one.
Eun Sook is exactly the opposite of his wife. She's quiet and girlish. She has become the reason for his living. He feels like he's a true man before her. As friends who give spiritual console to each other, they continue their sweet love story...
Soo Mi finally finds out her husband's love for Eun Sook. Soo Mi beats Bong Sup up. While being beaten up, he still says out loud "Don't insult our love!" Though he is thrown out of home after being beaten up, he at the end returns to his brave wife. Soo Mi and Bong Sup overcome several obstacles and still lead their marriage life, sometimes wrangling and squabbling.