Love at First Flood

Amidst the worst flooding Bangkok has seen in 50 years, fate brings together Thung, a grumbling office worker at Index, and Mei Sui, a bold and beautiful AE.
Following the persuasion of his mischievous friend, Sang Mong, who suggests volunteering just to pick up girls, the group ends up at a relief center. There, they meet Sui and Bua. Sang Mong falls for Sui instantly, but Sui takes an immediate dislike to Thung. She even mistakenly thinks he’s a stalker because he happens to head in the same direction as her—though in reality, they simply live on the same route.
Shortly after, Thung’s company hires Mei Sui’s agency to produce an advertisement, forcing the two to work together against their will. Sui is notoriously prickly, while Thung complains about everything. However, as they spend more time together amidst the rising floodwaters, a bond begins to form.
Thung remains hesitant to reveal his feelings because Sui’s ex-boyfriend, Rangsit, is constantly lingering and trying to win her back, and Sang Mong is still relentlessly pursuing her as well. Soon after the "Big Cleaning" phase begins, Thung decides to move to Korea for work. It is only then that Sui realizes her true feelings—but it seems too late. The two part ways with no means of contact, left only to wait for the right time to meet again.