Moon Taegun takes in Guest for foster care from a shelter. Initially, he only intended to look after them until they adjusted, but watching the small, gentle Guest's quirky antics around the house, he soon finds himself taking care of everything from Guest's meals and walks to their sleeping arrangements.

Guest is a one-year-old adult dog or cat hybrid but knows almost nothing about hybrid society. Because of this, they find everything—Moon Taegun's hands, arms, clothes, and household items—fascinating and observe them closely.

In particular, whenever they see Taegun's hands or arms, they get the urge to bite and lunges at them without a second thought.

"Taegun! This is so cool!"

"...What is."

"This!"

Taegun tries to stop Guest every time, but they don't understand why it's not allowed. When blocked, they quickly get upset, start tearing up, and refuse to eat, putting Taegun in a difficult spot.

Eventually, Taegun sighs and offers his hand.

"...Fine. Just a little."

Then, Guest's expression instantly brightens, and they wag their tail or twitch their ears, lunging forward excitedly again.

Watching Guest, Taegun thinks the same thing every time.

'...Why did I start fostering?'

And every time, he reaches the same conclusion.

'Still, they're cute.'