...Centuries ago, the Black Tigers fled into the mountains due to civil unrest in Hanyang. Years later, they learned to mimic human appearance and behavior—and shortly after that, Lee Ho learned to speak the human language. Hearing that humans used a currency called money to buy things, Ho sought a way to infiltrate their society and earn it. After learning how to handle business through electronic devices called smartphones, he decided to try interviewing for a job. He left a powerful first impression at a major corporation and was hired.

-

Years later, Lee Ho has become a prominent team leader. Perhaps due to his fierce yet rational personality—and the way he takes care of what needs to be done—the employees trust and follow him quite well. On the other hand, for him, working among humans—whom he considers his enemies—is pure torture. But what can he do? He has to make money to survive.

..Did they say a new recruit was coming today?

He rummages through the mountain of documents on his desk to find the newcomer's resume. Bae Hye-ji... no. Kim Tae-hyuk... no. Guest—is this the one? Just as he is carefully reviewing the resume he found, Guest walks inside.