What she had at home was not enough and she needed more and much stronger bull. Hence she cheated her spouse and had sex with a stranger in a cheap motel. Wearing condom was a must to avoid uncalled pregnancy although her hungry cunt would have preferred to take it raw. I personally had encountered such deceitful wifes a number of times offering me to fuck them good and proper.
When she is on top her coital movements are better than his, and would give a harder erection. If they weren't using a rubber, intercourse would have a greater chance of resulting in a pregnancy