I am jealous of your husband. I always wanted to have "sloppy seconds" with my wife, me being second in line too that is.
I always felt odd for feeling that way, until I was watching "Top Cops", a real life police program they had here in the states back in the late 1990's...and they were doing a sting operation and were using a decoy prostitute to lure men willing to pay for sex so they could arrest them. Anyway, this one guy came up to the undercover police officer/prostitute and asked her how many men she had been with that night, and when she said none, he said, "I'll come back after you have been with a few." It was then that I realized I was not alone in thinking this way.
Even under performing, your husband now knows what sloppy seconds is like, something I wish I could try!