It's based on the anime by the same name.

Hibiki Amawa is an ordinary working stiff, but he can't seem to get a job – or pay his rent. When his volatile landlady goes ballistic and threatens to kick him out by the end of the day, his desperation to find a teaching job reaches a critical level - and he pursues a job he couldn't get before - as a PE teacher at a local school. The catch is that the school only hires female teachers!! So, with a crash course in fashion and a special voice modulator, Hibiki slips right into his new role as Ms. Amawa – with surprising results!