Taeju's Brother, Taehee

With her wedding ruined by the groom's secret girlfriend barging in, Kang-Wu crashes at her best friend Tae-Ju's place, not expecting to run into her little brother Tae-Hui in the morning. Despite their awkward first encounter, Kang-Wu finds him to be perfect little brother material. But after he protects her from her obsessive ex's harassment, she sees him in a different light. He's tall and good-looking, he's a great cook, he's funny, he's sweet... Wait, has Kang-Wu already fallen for Tae-Hui?!

(Source: Tapas, edited)