A stiletto as in strappy high heel womens shoes...
LOTS of escorts get into tina because it a). It keeps you up and available to keep working b). It keeps you slim c). It can make sex easier with less inhibitions d). If you can get clients to do it with you, you can milk them for hours of "play" and thus bigger pay.
It also rots your teeth and brain, causes to to make bad decisions, and after a while destroys your muscle mass; just to name a few adverse side effects. Some of the muscle guys on Tina keep up at the gym and pair it with steroids and growth hormone to keep up a decent appearance. But you start to see it in the face and attitude pretty quickly.