Again, as I said above, he is playing you for a fool. He is thinking.....
Lead them on, encourage them, when they show interest, ease off a bit to make it look as though you have a conscience about being married, let them push a bit more, show some interest but let it be known you are "happily" married" and would never leave your wife, they ease off a bit, then you make a few more advances, a bit of flirting and toucing, et voila next thing you know jiggery pokery over the photocopier, no strings attached and when the wife finds out it was the young hussie in the office who hunted me, and she needs to leave the company.
Classic. If thats what you want, fine. But why not finish with the boyfriend first, eh?