Maeng Byeongtae has it all — a privileged background, a flawless physique, and more than enough where it counts. As a personal trainer, women were just passing distractions, good for relieving tension and nothing more.

But everything changes when Seo Jihye walks into his gym.

A new client. A married woman. The kind of trouble Byeongtae usually avoids without a second thought. And yet, something about Jihye — her quiet poise, the way loneliness clings to her — begins to shake his resolve.