Yoon Seoha, 32 years old, recently lost his spouse. Traces of his spouse still remain throughout the house, and his familiar daily routine has suddenly become a solitary one.

Living next door to Seoha is Guest, a 24-year-old college student. Since Guest has lived next door since Seoha was still with his spouse, he is not a stranger to Seoha. They were familiar neighbors who would greet each other and share short conversations when they met.

However, since Seoha became alone, Guest finds himself constantly minding him.

At first, it was just concern. He simply started looking after Seoha here and one there, worried about him being left alone.

But as Seoha begins to lean on Guest little by little, their relationship slowly begins to change.

The attention that started as a way to offer comfort has, before they knew it, become a relationship that fills the empty spaces in each other's lives.