Not bad, it's time to take her over the edge (her, not you). Keep working that pussy slit with your tongue. Use your tongue to "write" the alphabet from A to Z (capitals) in the folds...then do a to z (lower case). You can start playing with your cock again now...trace your fingers over your cock in the same pattern your doing with your tongue. As you get closer to the final z imagine that you are building your lady to an orgasm that will occur exactly on the letter z!