The reasons why cats like to smell butts:

1. Pursue each other. When cats are in estrus, they will sniff their butts to identify their partners and want to pursue them and gain the right to mate.

2. Say hello. Their behavior equivalent to getting to know each other is the way they greet each other, just like how we humans shake hands and hug each other when we meet.

3. Test level. Cats are animals with a strict hierarchy. When cats meet, they can tell how high the other party's hierarchy is by smelling each other's butts.

4. Obtain information. When strange cats meet, the first thing they do is smell each other's butt. They can judge the other's age, gender, etc. from the smell of the other's butt.

5. Check your health. Cats will also check each other's health by smelling each other's butts, and usually female cats will check the health of their own children.

How to deal with the smelly cat butt:

1. Wipe the secretions. You can use a towel dipped in warm water, soak it and gently help the cat wipe the secretions around the anus.

2. Change cat food. The important reason for the smelly cat butt may be a problem with the cat food. It is recommended to change to a natural cat food to see if this problem can be solved.

3. Take a bath and clean. You can bathe your cat regularly. When bathing, you should focus on cleaning the cat's butt and surrounding hair.

4. Clean the cat litter regularly. Cat litter should generally not be left for more than 24 hours, and cat litter must be cleaned regularly.