Years ago, I learned from a "professional" girl that she kept a middle fingernail trimmed down to the finger tip, allowing her to insert her finger anally into any guy she was performing oral on, and making him have a great time, while "greatly accelerating" the process ("time is money", was her quote).
I immediately took her tip and for years have kept my middle fingernail trimmed totally back. My nails are always very manicured (I tend to go with "French Nails") with just that one nail super short. Very few people have ever noticed or asked why.
My hubby knows, of course, and when he holds my hand or kisses my fingers, I know he greatly appreciates the effort I put in to being always ready to please him that way. It is a constant "in your face" reminder of my love and sexual prowess...for us both.
On the very few occasions when I wanted to look "more symmetrical" (a Black Tie affair for our work), I had my manicurist apply a stick on nail tip/extender and it looked fine, on that one finger).
Anyway, my simple question. Does anyone else do this? Does anyone here keep a finger "prepped and ready" for play?