It sounds like a hot spot, which can be due to various different things. It can be due to allergies, though if he is not showing other symptoms then that isn’t terribly likely. Have you tried any new foods lately? The most important thing right now is getting him to stop chewing on it, which unfortunately may require him to wear a cone or cone-alternatave. You could try a soft or inflatable cone if he doesn’t try to reck it and it stops him from going at the spot. You could also ask the vet for advice. If this reoccurs or if he shows other signs of being itchy or hair loss, then allergies, either food or seasonal, are likely.
