Well, as a massage therapist, I have had ticklish reactions. While normally I'll just excuse myself and apologize for the reaction, if I know the client well enough and got a bit of a "friendship" with them, I'll sometimes tease them. One of my client has super ticklish feet, and when I go to lift their ankles to put a bolster under their ankles, sometimes I'll sneak in a quick tickle. They are funny, and they are more than okay with it, so it's been fun to do that to them. lol