Dark Triangle by Dale Greggsen

'Love between two women can be a bond to be broken only by death--or by another, more alluring woman!'

Back cover:
The body girls...

To work for the Lovely Lady Health Clubs, a girl's body had to be perfect - and her morals non-existent.

For the clubs were more than figure-building salons. They catered to women who needed and wanted more than exercises...women who hungered for the most warped kinds of emotional and sexual fulfilment.

Toni Hart walked into her job with her eyes wide open, ready for any kind of task her superiors might ask her to perform. She knew she was different from the other girls, and she didn't mind putting that difference to work for her advantage.

Then she met Dottie Harris - the woman who was going to be both her mistress and her master. And she found herself involved in one of the strangest triangles of all time...