My Oscar did that when he has cystitis...I think it was because that was where it was uncomfortable, and he was licking it to try and make it feel better.

I hope dear Gato is not blocked! A couple of kitties here have had their bladders go into spasms, and are on amitryptiline for their problem. This drug is used for the same reason on humans!

I and others here have had very good luck feeding our cats grain-free dry food. It apparently keeps the urine pH where crystals do not form. Also - I use filtered water; someone here posted that if your area has hard water, minerals in it can be a factor in crystals forming.

Sorry to overwhelm you with stuff - prayers that Gato is treated and is back home with you soon!