Ore ga Onna ni Somaru Made The Motion Anime

The hentai protagonist, Chloe, is suffering from a severe flu. She wakes up and realizes that she has transformed into a girl. Her memories remain the same, only her body has changed. Distressed, she explains her situation to the owner of the cafe where she works before the transformation. The owner and some of the employees are skeptical and decide to see for themselves that she is now a girl.