A flashback from the past is shown at the beginning of Branding in Seongsu Episode 19. In the previous episode, Eun-ho had asked that Na-eon remember how they first met and offer him her sincere apology if she wanted him to stop trying to conspire against her. We delve deeply into their first encounter after receiving some background information.
Back in the past, we find out that Eun-ho wished to recruit Segye agency to promote Bandi Incense, the incense company that he and Da-eun built. For many years, he and Da-eun worked diligently to develop a unique incense brand that still uses time-honored techniques to create its distinctive scent. We see that Da-eun has always wanted this company to be a worldwide success, and so Eun-ho is working tirelessly to make her dream a reality.
Consequently, Eun-ho goes over to Segye agency to hand over the marketing responsibilities. Nevertheless, he is stopped at the entrance and isn’t allowed to pass. Following this, he comes across Na-eon, who makes her way to the Segye agency to promote Charmant, the agency’s scented brand. After the collision, they manage to muddle up each other’s papers.
Unfortunately for Na-eon, the man she crashed into has all of her presenting materials. However, she still manages to impress the Segye group—including director Yi-jae—with her presentation. In any case, director Yi-jae has agreed to greenlight her proposal—but only if she can discover a unique scent within a week. Meanwhile, Eun-ho discovers that Na-eon has his brand paperwork. As a consequence, he makes a beeline to Segye agency to retrieve it. However, the security personnel won’t let him in.
Following the meeting, Hee-jung encourages Na-eon to do her very best. Additionally, she assures her that she will be promoted to team leader after completion of the project. Following this, then we witness Na-eon putting in countless hours to secure the promotion. Furthermore, she mimics Eun-ho and Da-eun’s brand proposal and uses their traditional scent, which is their signature feature.
After this, word gets out that Segye agency is using the conventional perfume of the Josean era, and the brand does very well in the market. Conversely, Eun-ho and Da-eun are struggling to accept the collapse of their brand, which they had worked tirelessly to build over the years. A candle mishap claims Da-eun’s life, exacerbating the situation.
As a consequence, Eun-ho has a hard time accepting the truth that he has lost his best friend. He subsequently gets in touch with Na-eon and confronts her regarding the theft of their brand’s proposal. After that, she gives him a week to gather proof that she is innocent.
Before their presentation in the present timeline, Na-eon and Eun-ho experience yet another soul swap. The two of them then turn on each other. However, before anything worse happens, Na-eon pulls Eun-ho outside the meeting venue. The episode then concludes with Na-eon confronting Eun-ho about her past transgressions.
In episode 19, the past takes center stage as we learn the reasons behind Eun-ho’s animosity towards Na-eon. The fact that Eun-ho and Da-eun’s brand idea was taken by Na-eon is revealed. Furthermore, Na-eon’s actions caused Eun-ho to lose his best friend.
We primarily focus on the past for the majority of this episode, and the show’s storyline appears to be heating up at this point. Now that everything is falling into place, the characters and their journeys make a lot of sense. Still, the show’s supernatural elements are its Achilles’ heel; they make it look so far from reality that you can’t take it seriously.