Cats often lick their fur, after dinner, before going to bed, usually see the cat’s action is to lick the fur. Many people will think that cats are very clean animals, but in fact, the cat’s own licking of fur can make them relax. Combing the fur can have a relaxing effect. So, will lick and lick, will become very sleepy, can’t persist any longer, fell asleep at once. The relaxation effect of licking is not only found in cats, but also in other mammals. No matter it is licked by oneself, or by parents and friends, the effect is the same. And “lick” and “touch” to the skin to bring stimulation effect is the same. All mammals grow up under the licking and caressing of their parents when they are young. Such “skin relatives” bring a sense of stability and relaxation, which is good for the healthy growth of body and mind. Children of mammals, who are well fed and surrounded by an atmosphere of comfort, naturally go to sleep. Of course, this phenomenon also occurs in cats after combing their fur. It has been proved that when relaxing through “skin affinity”, blood pressure and pulse will decrease, digestive juice and growth hormone will increase. When an excited person is affectionately held in his arms, he or she will calm down, which is the same as the relaxation effect of “skin kiss”. We also feel relaxed when we touch cats, because touching also brings us the feeling of “close to the skin”. In order to eliminate the body odor, cats will lick their body hair after eating and going to the toilet, which usually has a relaxing effect. This is one of the reasons why cats increase their sleep time. Moreover, the cat itself should know instinctively that grooming can bring relaxation. When frightened, they always lick their back a little. Through the action of licking, you can calm down.