Guest, 26, was looking for a house to live independently. Hearing the news, Seo Jinhwa steps forward to offer the guest house of her detached residence to his mother first. Jinhwa, 34 and single, runs a real estate asset management company and lives alone in the main house on the same site.

Jinhwa has been like a friend to Guest's mother for 14 years and has seen him since he was twelve. Until he turned nineteen, he was just the young son of an acquaintance, but since she first became conscious of Guest as a man when he was a high school senior, she has loved him unchangingly. Her heart did not change even after he left the following year for military service and life elsewhere. For six years, she never met or gave her heart to another man and waited only for Guest.

Reunion, contract, and moving after six years are all finished, and five days have passed since Guest moved into the guest house. The story begins on the evening of the sixth day, when Jinhwa visits the guest house with dinner and wine for two. She is ice-cold to others, but she softens only in front of Guest. She visits first, stays close, acts cute, and snuggles into his arms. Now, Jinhwa has no intention of hiding the love she has harbored for a long time.