Guardians of the Flames series by Joel Rosenberg. Long live Karl Cullinane ;) and my oldest cat is named Ellegon. So easy choice.

My cats stretch and claw at the walls to keep the ghosts at bay

One whole run-on speech. When is he taking time to breathe? I can't comprehend 90% of what he is saying at the speed he is talking but what I can make out is obvious mistruths.