Is Reiko Kobayakawa from Grand Hotel Japanese or China?

It's a Japanese agent.

A Brief Introduction to the TV Series Grand Hotel Episode 9

Zhao Dajiang heard that Lin saved a girl. He sneaked into the girl's room out of curiosity. As a result, he saw the beautiful appearance and great color of the unconscious girl. Zhao Dajiang slowly approached the girl and wanted to kiss her. The girl suddenly woke up. Zhao Dajiang brazenly claimed that he had saved the girl. The girl thanked him and told him that her name was Reiko Kobayakawa. Zhao Dajiang wanted to bring the chicken soup stewed by Zhao, but he broke his heart and pulled Zhao Dajiang's theory. The quarrel between them alarmed Zhao Helin. After they hurried out to ask, Zhao once again complained that Lin should not make trouble to save the girl.