I did practice on things to improve my gag reflex and other skills, I like the purple dildos that are made by tantalus, or the name might be Tanya’s...
My spouse very much dislikes semen, to the point that she very often spoiled my orgasms. But for whatever reason she would get excited if a "leaked"...
I'll concede to a fascination with precum. I suppose that owes to the fact that, even when fully aroused, I've never produced more than a bead or two...