In this chapter, we learn that purity is lost when a man has sex with a woman. If two men have sex, one of the men's marks will disappear, and the other's will remain. In other words, if you're a doctor and you see a beautiful woman in front of you, it's time to take a look at your patient. The doctor tells the patient to roll up his sleeves, because there's nothing wrong with his skin. He's just a doctor, after all, and he's been practicing medicine for a long, long time. He says that his patient's skin is fine, but his blood circulation isn't going well, so he'd better hurry up and get his blood flowing again. The patient is terrified, but the doctor reassures him by saying that his skin is smooth and healthy, and that he'll be fine in the future. He then says that the doctor's going to leave the next day, so the patient should be careful not to make a big fuss about it.