So many reviews of other shows talking about great chemistry but none got actual boyfriends chemistry as right as this one. The MLs bickering, playfulness, teasing, cuddling and overall behavior with each other totally scream boyfriends loud and clear, even some of the side characters comment on this.
The delivery is simply effective and convincing,

Short, lighthearted and fluffy with balanced power dynamics, no toxic shenanigans at all. No character dominates over the other or manipulates. They equally tease each other and equally need each other.

Initially Ki Tae appears to be the cold one who rejected Lee Wan and now "bullies" him in the work place but Lee Wan takes no bullshit and assertively talks back swiftly killing the Jerk x Doormat trope out of the show.
Fortunately, soon it's revealed how they both never moved on and how much both always liked and need each other. Two cinammon rolls really.

Poorly used beautiful soundtracks though, Because of You by Cheero is one of those that could make you cry.