Mars in hard aspects to Saturn in a man's natal chart shows that he has repressed anger issues. Often, his desires are frustrated in some ways and this manifests as anger. Outwardly, he may appear calm and controlled but inwardly, he is seething with rage. This is a man who struggles throughout his life because he always finds that his efforts are often met with obstacles and resistance from others. He is always fighting, fighting a battle against the rest of the world. As a result of bitterness in his heart, he becomes a bit of a bully, constantly picking on others, needling them, criticising others or challenging them. They become very hard on themselves and others. They are noted for their ability to work very hard and slave around the clock patiently in order to produce work of the highest quality. They are cruel taskmasters.
As a child, the Mars-Saturn man suffered excessive punishment and discipline at the hands of a parental figure, most likely the father (in a woman's chart, it's usually her mother). Due to the cruelty he endured in the hands of his father, he will develop animosity towards authority figures throughout his entire life. He will go into conflict with bosses or managers or people in charge. He works better alone and is often gifted with great entrepreneurship and business skills. Because Saturn is constantly testing them, beating them up and putting obstacles in their path, some of them eventually gave up on life. I do feel with this position, one either grow overwhelmingly strong to overcome Saturn or they totally give up trying as Saturn is crushing their will to live.
So how does the cruel taskmaster perform in bed? They might be met with sexual rejection, frustration or even sexual inhibition in the early part of their lives. They can't express what they want easily. They may be late bloomers. The effect is almost similar to a very young Capricorn - sexually repressed, nervous, insecure and getting their panties all twisted up in knots when it comes to expressing their sexuality. They have a fear of rejection when it comes to relationship, and a stronger need to be in control. This eventually leads them to become domineering in their relationships.