Chae Yoo Jin and Han Gijun

Intelligence and Eloquence: He is handsome, quick-witted, and possesses a "silver tongue" with formidable powers of persuasion, which helps him succeed in the spokesperson's office at the Korea Meteorological Administration (KMA).
A "Model Student" Mentality: Having lived his life as a model student, he struggles significantly with failure and often has a hard time coping when things don't go according to plan.
Ambitious but Struggling: After a difficult start to his career, he gets scouted for a prominent position. His ambition often drives his actions.
Relationship Challenges: He is the ex-boyfriend of the main character, Jin Ha-kyung (played by Park Min-young), and their relationship conflicts are a key part of the show's initial plot.
Government Affairs Role: He works in the government affairs office, a role that aligns with his skills in communication and persuasion. Shows through his actions he's a changed man

Ambitious & Career-Focused: She's driven in her reporting work and seeks success, even if it means challenging her relationship with Shi-woo.
Pragmatic: She values stability and a comfortable life, which influences her decisions, including her eventual marriage to Ki-joon.
Conflicted: She struggles with balancing her romantic feelings for Shi-woo with her desire for a secure future with Ki-joon, leading to internal turmoil and external drama.
Entangled: Her personality often manifests in her messy love triangle, as she's caught between the free-spirited Shi-woo and the more grounded Ki-joon. she has a change of heart to change through her actions.