Sounds like your female is really easy going to give free rides. The male sounds like he is afraid to jump off though, as that is the most common moment for cannibalism to occur; however, the longer he stays there the more likely she is to get impatient and simply reach around and eat him.
If he is already mated he is just holding on for "dear life", in which case you should separate them. The most common way is to lightly grasp both the male with one hand and the female with the other by their thorax, which is often enough for the male to let go, if not pull very lightly. I find placing a index card between them and using a stick under the male to slowly/carefully pry him off the easiest - just keep sliding the card in with your hand as each leg releases.
excited for babies 
