Kanojo, Okarishimasu is a Manga/Manhwa/Manhua in english language, Ecchi series, english chapters have been translated and you can read them here. You are reading chapters on www.mgeko.cc fastest updating comic site. The Summary is

Kinoshita Kazuya dumped for another guy, he hires Mizuhara Chizuru from an app called Diamond to be his girlfriend to make himself feel better.