Because This Is My First Life

The landlord, Se-hee turns out to be a man who Ji-ho kissed; they can't live together.

Ji-ho accepts Se-hee's proposal; Se-hee takes his words back, but Ji-ho is still puzzled.

Se-hee suddenly proposes to Ji-ho, and so she asks him if he likes her. However, the man only offers to get married to get what they need. Yang Ho-ran indirectly proposes to his girlfriend Sim Won-seok, who has been dating for seven years, but she doesn't noticed that. Meanwhile Su-ji is asked by Ma Sang-goo, who she met at a company event, to spent the night together... Ji-ho goes out for a drink with her senior screenwriter, professor Hwang. There is also a director and Yeon-seok, who is drunk and harasses the screenwriter.

Ji-ho decides to go home because she lost her job. However, when Se-hee delivers her the script she left on purpose on the bus, she proposes him to get married. Ji-ho returns to the townhouse with Se-hee's consent. The two immediately set the conditions for marriage and greeted Ji-ho's parents. Ji-ho and Se-hee set a strategy to win the screenwriter's harsh father over. However, he already knows they're living together, so they face a difficult situation. On the other hand, Won-seok wrongly thinks that Ho-rang wants a sofa, because of Sang-goo.

Ji-ho tells Su-ji and Ho-rang that she is going to get married, while Se-hee also talks about the imminent marriage to his colleagues. The couple convinces the surroundings with a catching phrase on how good they are for each other, although their friends have some doubts about the sudden news. After talking to Se-hee's parents, all they need to do is to have a meeting between the two families, face-to-face. The couple, who decides to skip the wedding ceremony because it would be expensive, successfully completes all the secret maneuvers for their families' meeting. However, Ji-ho is worried because her mother's behavior is unusual...

At last, they decide to have a wedding ceremony for Se-hee's father and Ji-ho's mother. It's just a wedding to convince their parents, but Ji-ho cries when she reads a letter from her mother to the groom. Looking at Ji-ho's unstoppable tears, Ji-hee tells her "I'm by your side", as his mother-in-law has told him. Meanwhile, Sang-goo and Su-ji, who reunited as friends of the bride and groom, and Won-seok and Ho-rang, who haven't met since the sofa incident, will watch over their friends' wedding in an awkward and spiky atmosphere.