Its hard to pin down an exact percentage due to all the different circumstances. I really enjoy cunnilingus so much that I have spent 30 to 40 minutes out of an hour appointment just enjoying the ladies body. Plus as has already been stated. A lot of things are similar in my sessions but also each has different aspects depending on who what where and when. In other words I usualy just try to enjoy and if I don't feel that she is enjoying herself equally then the actual sex would be very minimal. i lose interest quickly if the lady is not into it.