Neko ni Naritai Tamagawa-kun (Anime) Wiki

For Tamagawa, volunteering at a cat café is the only relief from his stressful job. The manager tells him to, “relax and learn to be spoiled”, but he doesn’t know what that means until a new customer, Shindo Rai, comes to the café and tells Tamagawa he wants to keep him as a cat! Enter their strange, but fateful relationship. A pure-hearted and soothing romantic comedy.

(Kodansha, translated)