Marriage Not Dating is light, airy, and funny while also delivering a nice healthy dose of heart and depth. She finally bursts through the door to find him unresponsive, as a knife falls to the floor. Two days before the incident. One day before the incident. Mom just wearily sighs, not believing him. Hoon-dong texts Jang-mi repeatedly, getting no response, and perks up when he sees her riding up to his restaurant.
He plays it cool, but frowns when she only asks after Yeo-reum. Ki-tae reluctantly lets Jang-mi come in just until Hoon-dong leaves, which is apparently a big deal as he never has visitors, not even women. Ki-tae thinks on his feet and shoves Jang-mi into his bed, then half-undresses before going out to meet Mom.
Jang-mi tries to sneak past them into the kitchen, but Hoon-dong catches her mid-sneak. Ki-tae and Se-ah go on the date that she won in the auction, where they have a nice meal by a fancy indoor pool.
Jang-mi lets herself into her dark and empty house, and remembers a time when she was small and was left home alone, terrified and crying for her parents. She starts grabbing for fish with her bare hand, calling it Nemo. This scares Jang-mi so badly that she drunk-wails, so he caves and lets her make the ramyun. Why did he ask her to eat? She asks about Se-ah, and he just says they respect each other too much to ruin it with marriage.
He thinks she needs to be alone a while before dating again. They argue over which is better, closeness or solitude, until her phone rings. Jang-mi hides in the bathroom to talk, and Yeo-reum explains that what she saw was the tail-end of his charity date.
Relieved, she agrees to meet him, but Ki-tae has locked her in the bathroom. He refuses to let her out, since a guy will never like her if she goes running whenever he wants. In their struggle over the door, Jang-mi breaks the door handle and escapes, counterattacking: How can you find someone to be with, if you spend all your time alone? She yells that she never wants to be alone, and leaves. Day of the incident. Grandma says she understands why Ki-tae wants to live alone, the way they treat him.
He blames the ramyun, but she assumes Jang-mi is giving him a hard time and promises to talk to her. Right onto the pancake. Jang-mi fills him in on what happened, and he tells her to go and heads to the hospital.
Luckily Grandma is fine, only heavily sleeping off all the alcohol. Ki-tae angrily pulls Jang-mi aside to ask what she was thinking. Hurt, Jang-mi just quietly apologizes again and leaves. Ki-tae goes home and cleans up the mess, then relaxes in a hot bath and revels in his solitude once again.
Ki-tae spends 48 hours locked in the bathroom, reading, exercising, and fighting boredom. He weakens and hallucinates his friends and family saying how tired they are of him, knowing none of them will come and rescue him. For a moment he perks up thinking of Jang-mi, but remembers their fight and loses hope. He lies on the floor and passes out, just as we saw him at the top of the episode.
At home that night, Jang-mi breaks a glass and flashes back to being home alone as a child, where she broke a glass and cut her feet badly. As Jang-mi talks, Ki-tae rouses just enough to feebly call for help. She grabs a knife and pries the door open, dropping it when she sees him lying half-dead on the floor. She tries to rouse him, and he uses the last of his strength to clasp her in a tight hug.
Ki-tae falls into the memorial feast, scattering food everywhere, as a group of women try to hold Jang-mi off of him. D minus 4… Jang-mi helps a weak and stumbling Ki-tae to his car, headed for the hospital, even hoisting him up for a piggyback when he proves too feeble to walk.
They run into Se-ah, who was also worried and came to check on him, and Jang-mi explains how he was trapped in the bathroom for two days. Se-ah drives them to the hospital, barely containing her eyerolls as Jang-mi fusses over Ki-tae in the backseat.
Jang-mi says his family is on the way, and Ki-tae asks Se-ah to go while telling Jang-mi to stay. Jang-mi explains that he was locked in the bathroom and Ki-tae says she actually saved him, but only Grandma thanks her.
Aunt Mi-jung tells Mom that they should support them, if only because opposing the marriage will push Ki-tae towards Jang-mi even harder. Jang-mi protests but Mom says she should start racking up brownie points as early as possible.
Their identical glares of disbelief are a riot. Some patrons make a rude comment to Jang-mi, and Mom kicks them out. Mom pulls ready-to-go divorce papers out from under the register and prepares to sign, but Jang-mi stops her and agrees to help with the memorial.
All Jang-mi has to do is show her very worst self on the day of the memorial, and his mother will make him call off the engagement. It should be easy…all she has to do is be herself. He follows them and when they stop for lunch, Ki-tae just plops himself down at the table with them. He tries to intimidate Yeo-reum, who stays frustratingly unaffected.
Ki-tae texts Jang-mi to be careful, that his aunt may be spying on them. Jang-mi and Yeo-reum sit in the park, but Jang-mi is too twitchy and paranoid to enjoy herself, worried that Aunt Mi-jung is watching.
Dad and the young woman look awfully cozy, trading kisses and endearments and walking arm-in-arm. Jang-mi is in shock, and cuts the date short.
Left at the park, Yeo-reum sees Se-ah in her car and joins her. Se-ah asks what his relationship is with Jang-mi, but he just muses that she must be great because everyone seems interested in her.
Se-ah asks Yeo-reum to bring her information on the couple and offers him an envelope, which he accepts. D minus 1… At work the next day, Jang-mi considers whether she should tell Ki-tae that she saw his father with a woman. Mom points out that in her family, the women do all the work to prepare the food. She tasks Jang-mi with peeling a massive bag of chestnuts that night, and tells her to be at their house early in the morning.
She starts to tell Ki-tae that she saw his father with another woman, but he cuts her off. He suddenly turns cold and harsh and snaps at her to mind her own business, and it dawns on Jang-mi that he already knows. Jang-mi sarcastically apologizes and storms out. Later, Jang-mi sits outside, doing all the cooking herself. Jang-mi finally finishes some time later, and jumps up to do an athletic victory dance. The women eat and talk while Jang-mi does the dishes alone, mumbling about the unfairness of it all.
It stops his aunt from listening in, but Jang-mi drops her phone in the sink and ruins it. Finally everything is ready, and dinner is solemn and dignified. Ki-tae decides Jang-mi is being too quiet and asks his father to pour her some alcohol, knowing it will make her start talking and most likely say something unacceptable.
Dad tries to calm her down and she rounds on him, calling him the worst of the family. Jang-mi starts to say that she saw him with a woman but Mom stops her, and pulls her aside. Jang-mi, hurt, says that she could have sworn she was family given how badly they treated her. She overhears the women criticizing her parents, and asks Ki-tae with angry tears in her eyes if he told them about her family. Jang-mi snaps and starts to scream and hit Ki-tae.
The women try to pull her off him, and they scuffle until he falls into the table covered in memorial offerings. Jang-mi declares her work here done, and righteously stomps out of the house. She leaves him to face his family alone, and goes to meet Yeo-reum. In the closed restaurant kitchen, Yeo-reum cooks up some pasta for Jang-mi, who does her best to kill an entire bottle of wine by herself. She drunkenly admits that she was there just to create a scene, but moans that it became real.
She leans in close to say that actually… she just really really really really really worries about him. Then she passes out.
Meanwhile Yeo-reum and Jang-mi are asleep side-by-side in the dining room, her on a bench and him on a row of chairs. Ki-tae tries to reach Jang-mi but remembers that her phone was ruined, and speeds up to try to get to the restaurant before his mother does.