Real Underwear Body (1994)
Real Underwear Body is a 1994 Japanese pink film directed by Yutaka Ikejima and scripted by Kyōko Godai. Along with Takahisa Zeze's Dream of Garuda (aka High Class Soap Technique 4: Blissful Secret Play) it tied for the Best Film, 9th Place award at the 1994 Pink Grand Prix ceremony.
More at Wikipedia.