The Compete Keeper Chronicles
by Tanya Huff is a trilogy that includes Summon the Keeper, The Second Summoning and Long Hot Summoning. I am always impressed by this versatile author (and I am a really big fan of her space opera Valor series that features a truly kick-butt heroine and I enjoyed the glimpses of Canada that I received through her Blood series) and she has such a quirky sense of humor that I delight in the snark (featured most recently in the sequel to The Enchantment Emporium, The Wild Ways) although I undoubtedly miss some of the subtext occasionally. This omnibus is a bit unwieldy to handle (especially if one has wrist problems the way I do) but it is definitely a treasure of entertaining fantasy. I love the way the cats have their own way of dealing with rules and annoyances and that entertaining struggle between what the veterinarian has decreed for the health of the cat and the cat's own opinion is even funnier when the cat can actually vocalize his opinion! There is a lot of creativity in this series and although these books were initially written more than a decade ago, they are still just as refreshing as they were then. I can only hope that the author is starting up the series again as I love playing in this universe.
My Amazon review for The Complete Keeper Chronicles is at this link
(Note: The following are just a FEW of the books in the author's various series)