The Yellow Emperor asked, "How can we know the signs of a woman's pleasure?" Su Nu replied, "There are five indications, five desires, and also ten movements to observe their changes and understand the reasons. The signs are as follows: 1) If her face turns red, then slowly unite with her; 2) If her nipples become hard and sweat appears on her nose, then slowly enter her; 3) If she calls out, swallows dryly, or spits saliva, then slowly rock with her; 4) If her yin becomes slippery, then slowly go deeper; 5) If liquid comes out of her buttocks, then slowly pull out."
The Yellow Emperor asked, "What are the signs when a woman feels pleasure?"