Full Eclipse (1993)

The Los Angeles Police Department has a special team of officers who are experts in reducing serious crime. Their leader boasts exceptional results achieved in other large cities, even though his methods are decidedly unconventional. The reason is simple: the man is actually a werewolf.
At the 49-minute mark, Patsy Kensit and a man kiss passionately, then she kneels on a sofa and he takes her from behind. He pulls off her shirt and we see the outline of her breasts, but there are patches over her nipples. It’s still a very intriguing sequence. As they fuck, she grows animal-like fangs.