Starter Villain by John Scalzi

Inheriting your uncle’s supervillain business is more complicated than you might think. Particularly when you discover who’s running the place.

Charlie’s life is going nowhere fast. A divorced substitute teacher living with his cat in a house his siblings want to sell, all he wants is to open a pub downtown, if only the bank will approve his loan.
Then his long-lost uncle Jake dies and leaves his supervillain business (complete with island volcano lair) to Charlie.
But becoming a supervillain isn’t all giant laser death rays and lava pits. Jake had enemies, and now they’re coming after Charlie. His uncle might have been a stand-up, old-fashioned kind of villain, but these are the real thing: rich, soulless predators backed by multinational corporations and venture capital.
It’s up to Charlie to win the war his uncle started against a league of supervillains. But with unionized dolphins, hyper-intelligent talking spy cats, and a terrifying henchperson at his side, going bad is starting to look pretty good.

In a dog-eat-dog world…be a cat.