Web of Seduction (1999)

There is one masturbation scene. The girl is fully nude and writhes on a chair. Her genitals are shown in close up. She masturbates in clear detail.

The movie opens with Tracy Ryan giving an erotic striptease/lapdance to a guy. She takes off her underwear to show full frontal nudity. We can see her nude crotch. Then she spreads one of her legs and shows her labia, seen in close-up. She then starts grinding her crotch on the man. Like this, Tracy Ryan shows off her genitals throughout the movie.

A woman seduces a man by lifting her dress up and showing him her bare crotch - pubic hair and vulva with labia visible. Then she strips fully naked and gets on his lap and they caress and bang in all sorts of positions