The manga from Reiji Miyajima began in 2017 and has twelve volumes to its name as of its anime announcement.
This one comes from the ninth episode where Kazuya is happy Chizuru got him a gift, but to her it’s just business.
The summer 2020 anime adaptation of the manga Rent-A-Girlfriend is underway with Crunchyroll streaming the series worldwide for audiences outside of Asia.