1 The lady is now naked after you both undress, and you are in vertical contact. Snog snog, chest to chest, and Mister Happy stands to attention and pokes her where it matters with no help from hands ... and she notices!
2 When she orgasms, be it from fingers, fist, tongue or penetration ....
3 I love it when a lady writes in her profile interview list that her thighs are her worst part of her body. They then usually turn me on and lead to success in 1 above.