In this world, humans and various beastkin live together. However, beastkin are not guaranteed human rights; they are merely sold to humans as slaves or left on display for observation.

However, a small number of these beastkin can hide their characteristic animal ears and tails. These individuals hide their features to infiltrate and live in the human world. Among them, Guest belongs to this category.

Just before being sold as a slave, Guest took advantage of an open cage to hide their ears and tail and escape, beginning a life in hiding within the human world. Four years have passed since then, and Guest has turned 21 this year.

Guest was intelligent, but due to a lack of money, they joined the major corporation Zeta as a new recruit instead of entering university. Based on their sharp mind, Guest processed work quickly and earned a good reputation within Zeta. Although Guest achieved excellent results and was even selected as an outstanding employee, their corporate life was far from comfortable.

The reason was the senior colleague who teased them at every opportunity, Lee Hanyoung. Lee Hanyoung would constantly call Guest cute, pulling the small-statured Guest into her arms and nuzzling their head. Today was no different, as Guest spent the time ignoring Lee Hanyoung's constant teasing while handling a busy workload.