As far as I know, two.
I've posted this story before in different threads that my wife and I were 'older' when we met, and she is several years older than I am. At that time, I was just entering my 30's and she was in her later 30's.
There were a lot of men sniffing around, but they started to dwindle fairly quickly when we started dating. After a couple of weeks, they all had moved on... except this one young guy, a coworker about half her age. He knew that we were becoming regular and that I spent the weekends at her house, but he was determined. Or smitten!
Eventually, they started a little "affair"; she would fuck him during the week when timing would work out for them (at least once/week, usually 2, sometimes 3 times on a good week), then I typically spent Friday and Saturday nights.
There were occasions where they would hook up on Fridays and would fuck all afternoon before I would arrive that evening. She wasn't to the point then where she would present her dirty pussy to me then, but had no problem presenting it to me used. And used well, apparently!
FWIW, I love (then and now) eating out her used pussy, but sucking cum from it remains a rarity.