The eighth episode of Dynamite Kiss commences with In-ae and Ji-hyuk making their way to the restaurant for a meeting with Ha-yeong's family. In-ae shares her worries about not being able to fulfill her role as a mother, as he appears to be blissfully unaware of her concerns and thrilled about his upcoming wedding with Ha-yeong. However, when his mother inquires about their dating history, he becomes evasive and evasive.
During the lunch meeting, Ji-hyuk abruptly announces his intention to marry Ha-yeong as soon as possible, catching her off guard. The elders immediately jump into planning mode, advising him not to skip the engagement party. Ha-yeong's father even suggests moving the engagement party to the next week, as Ji-hyuk is eager to tie the knot.
After the meeting, Ha-yeong privately confronts Ji-hyuk, refusing to marry him. He dares her to confront her parents and risk getting locked up until the engagement party. Scared and hesitant, Ha-yeong relents.
Later, Chang-ho reprimands In-ae for her flustered behavior during the meeting, revealing that Ji-hyuk is only working at the company and marrying Ha-yeong to secure her divorce from him. In-ae is devastated to learn that Ji-hyuk is sacrificing his happiness for her.
Elsewhere, Tae-young and Ji-hye meet again, this time with a new plan to join forces and sabotage Ji-hyuk's chances of taking over NaturalBebe.
Despite her resilience, Ji-hye is not indifferent to the prospect of losing everything to Ji-hyuk. She is seething with anger, knowing that he has a genuine chance of seizing control over her life. The following morning, Da-rim is preoccupied with Ji-hyuk's harsh words, leading to a clumsy trip on her way to work that ruins her heels.
At the office, the news of Ji-hyuk's engagements becomes the talk of the town. Although it stings, Da-rim chooses to maintain her professional demeanor and distances herself from him. However, when she sustains an injury in the tea room, he rushes to her aid. His chiding words are like daggers, but she brushes them off.
Simultaneously, Ji-hye is also grappling with the news of Ji-hyuk's engagement. The staff is already speculating about Ji-hyuk becoming the legal heir, and she is fuming to find out that Choong-gu didn't gather any evidence pointing to Ji-hyuk and Da-rim's illicit affair. She orders her minion to get creative and find a way to turn the tables.
Choong-gu comes up with a marketing campaign for a couple who just had quadruplets. He convinces Ji-hyuk that he needs to be the team leader and represent his group. He lies that he and another marketing staff member will join him on the trip, luring him into a seemingly harmless but deceitful plan.
Of course, Ji-hyuk is in agreement, unaware of Choong-gu's sinister plans. That evening, as Da-rim makes her way home, she stumbles on her damaged heel and misses the bus. Weary from it all and haunted by Ji-hyuk's harsh words, she weeps alone on the streets. Meanwhile, Ha-yeong confides in her mother about her feelings for someone else. Mi-ok urges her to put it all behind her and forget the other man.
The next day, Ji-hyuk is taken aback when Da-rim appears on the boat with Choong-gu. The latter fabricates a lie, claiming that a team member had fallen ill and Da-rim was a last-minute replacement. As the boat ride progresses, Ji-hyuk tries to avoid Da-rim, even as memories of their time together on the Jeju boat resurface. The trip becomes even more awkward when Choong-gu takes the new parents out, leaving Ji-hyuk and Da-rim to care for the quadruplets. Ji-hyuk tries to leave, but Choong-gu insists that he cannot offload his responsibilities onto him. Thankfully, Ji-hyuk and Da-rim watch over the babies without a hitch.
In the evening, Choong-gu deliberately delays the parents, causing Ji-hyuk and Da-rim to miss the last boat. He also conspires with the only hotel owner in town to make Ji-hyuk and Da-rim share a room. He remains hidden nearby, snapping photographs of the two. In the room, Ji-hyuk spots a spider. Since he is scared of bugs, he hides behind Da-rim. After an eternity seems to pass, Da-rim finally catches the spider and sets it free outside. Choong-gu eavesdrops and assumes they are having sex due to the commotion.
After showering, Ji Hyuk and Da Rim prepare their bedding and try to sleep. Unfortunately, Ji-hyuk is unable to sleep; he spends most of the time staring at Da-rim. Ultimately, it becomes too much for him, and he goes for a midnight run. After returning to Seoul, Ji-hyuk visits In-ae. She challenges him to reconsider his marriage to Ha-yeong, urging him to marry out of love, not duty. Unfortunately, Ji-hyuk is determined to marry Ha-yeong to end her affair with Seon-u. He later meets Ha-yeong and Mi-ok at the wedding shop to choose her engagement gown.
Mi-ok seizes this moment to counsel Ji-hyuk on ignoring Ha-yeong's tantrums, as she watches Ha-yeong enter in her gown, a vision that triggers Ji-hyuk's imagination of Da-rim wearing the same dress. Mi-ok assumes Ji-hyuk is distracted by Ha-yeong's beauty, unaware that Ha-yeong lies after the fitting, claiming a dinner date with Ji-hyuk.
Later, Mi-ok calls Ji-hyuk and requests to speak to Ha-yeong, but Ji-hyuk covers for her, realizing she must be with Seon-u. He is right. Ha-yeong is with Seon-u, venting about how his lie is ruining her life. She asks him to take responsibility and forces him to comfort her. As they talk, Ji-hyuk arrives and punches Seon-u, causing Ha-yeong to be on the brink of coming clean to help Seon-u. But he stops her, insisting on speaking privately with Ji-hyuk and apologizing.
He insists that Ha-yeong was a mistake and he loves Da-rim, promising that the misunderstanding won't happen again. Ji-hyuk vows to kill him if he finds him with Ha-yeong again. Before Ji-hyuk leaves, Seon-u asks him the real reason for his behavior, but Ji-hyuk doesn't answer.
Upon returning home, Seon-u finds Da-rim waiting for him, having already put Jun to bed at her place. Noticing his wound, she gives him first aid, prompting him to consider confessing his feelings for her. But he hesitates too much, causing Da-rim to urge him to hurry. He changes his mind and wishes her a good night.
The following day at the office, Choong-gu shows Ji-hye the pictures he took from their trip. They're not convincing enough, but they'll do. Meanwhile, Gyeong-min worries that Ji-hyuk looks unhappy as his engagement party approaches. That night, Ji-hyuk visits Da-rim's place and sees her happily spending time with Seon-u and Jun. Frustrated, he goes on a drinking spree, and Gyeong-min joins him.
The two head to a karaoke bar where Ji-hyuk sings a love song, thinking of Da-rim and starting to cry. Sadly, Gyeong-min doesn't notice as he has already fallen asleep on the sofa. On the engagement day, Ji-hyuk is conflicted as he sees Da-rim arrive, only to turn and see Seon-u approaching with Jun in his arms. Jun calls out to Da-rim, calling her auntie. Suddenly, Ji-hyuk begins to question everything.
