Our son invited his friend to stay the weekend with us during a college break. Tyrell is a handsome young black man we had met before. I couldn't help but notice how friendly and motherly my wife Cora was to Tyrell on the occasions we were around him. It seemed a little odd but I dismissed it. I awoke in the middle of the night to realize Cora was not in bed. I looked at the clock. Almost two a.m.. Strange. The light in the ensuite bathroom was not on. After laying there for a moment wondering I got up and went out into the hallway. I could faintly hear voices coming from downstairs. I approached the landing which provided a view our our living room. Although no lights were on, moonlight from the window gave me a startling view. Tyrell was sitting on the sofa with his back toward me. Cora was straddling him, her hips bouncing up and down, causing her breasts to do likewise. Her head was thrown back and she was obviously nearing orgasm. I was locked in a trance like state watching my wife fuck this young black stallion more than half her age. She slowed her pace a little and they kissed passionately. I was in disbelief but realized my own cock was getting hard at the sight before me. Cora again began riding him harder and moaning softly as she slid up and down his cock. Suddenly she saw me and our eyes locked. Instead of pulling away from him she paused only briefly and then continued fucking him, never taking her eyes off mine. Then she quickened her motions and with a loud groan, she came like never before. In all our years of marriage I'd never seen her experience such an intense orgasm. After she finally regained her composure she continued looking at me, not saying a word. Tyrell was completely unaware that I was watching him fuck my wife. I quietly returned to the bedroom. A while later Cora came back to bed. We have never spoken of the matter.