It's not recommended to touch a cat's belly, especially if you're not familiar with the cat. Cats are very wary, and their bellies are a vulnerable and sensitive area. Suddenly touching a cat's belly, or touching the belly of a cat you don't know well, can easily result in being scratched or bitten. 
Precautions for touching a cat's belly:
1. Cats don't like being restrained when they are walking, eating, or jumping around, so you shouldn't touch their bellies.
2. When a cat starts to show a more relaxed state, you should use a special belly-rubbing technique to touch its belly.
3. When touching a cat's belly, remember not to use too much force or force it, otherwise it may cause injury.
