I've read it a while back and can't remember. From what I remember theres only 1 episode and a rather short one, the manga was only about 8 chapters roughly give or take at the time.
The protagonist(male) enters a hotspring run by a group of girls. He wasn't supposed to enter the bath yet as the goddess was bathing and if she was seen she'd lose her powers. One of the girls didn't tell him he couldn't enter the baths yet and they meet. Theres a little blonde girl in there.
The OVA had
http://myanimelist.net/people/6560/Satomi_Satou as the goddess. I tried look through it from MAL but since it's only 1 ep, didn't have any luck.
In the OVA, at the end the protagonist had to take a bath outside with two male cats while the female cats/girls took a bath inside.
Any ideas on the name of this manga/OVA?