Ji-on Lee, an accountant with nine years of experience who staunchly adheres to a no-marriage policy, opts to take a long-awaited break after feeling drained from her job. However, during her well-deserved time off, she encounters a mysterious younger man who has just settled in next door. While he appears to be harmless, his daring and suggestive approaches start to challenge her determination… Will she be able to maintain her single lifestyle, or will her heart lead her in an unforeseen direction?