So last night, my wife is riding me reverse cowgirl, bent forward at my feet.
I had a small double tipped massager nearby for foreplay. Without asking, I put a little lube on one tip, then stuck it in her ass. She started moaning even louder. She loved it! Drove her crazy. I figured it would.
Sadly the battery ran out, but since she was enjoying it, I used my thumb for a bit.
I love it that my wife enjoys ass play.