One of my fondest memories is a yoga tickle. I was taking a yoga class in college. We were learning a pose of bending backwards completely exposing the upper body for tickling.
I was practicing the pose so only heard a woman in the class explode in hysterical laughter. When I looked there was another woman standing next to the woman who was lost in laughter.
The other woman rather sheepishly said, "I couldn't resist taking advantage and tickling her. I wondered if I'd discovered a female ler.