Sydney plays with her slave, she makes him feel good. After the slave had a good time he is much more sensitive and the she uses this to him hard! Sydney knows that her comfort hurts the slave. Meanwhile, the slave's mouth is close enough to serve as an ashtray!
The beautiful Tatjana is at least as sadist as beautiful. She tramples on her slaves groin in shoes. Tatjana really enjoys her games in which the slave is suffering. Real surprise that slave is cumming after this amount of pain and suffering.