One of the most intriguing things about King Ezekiel is his tiger sidekick, Shiva. Despite how useful they could be, animals are a rarity on The Walking Dead because more often than not, they end up zombie chow – audiences have seen more than one horse destroyed by a zombie horde. So the sheer amount of horses and pigs populating the Kingdom is surprising to see in and of itself. But Ezekiel's tiger seems even farther outside the realm of possibility. So how does King Ezekiel have a tiger on The Walking Dead?
Perhaps even more surprising than the existence of a tiger in a peaceful post-apocalyptic community is the fact that Shiva seems so well-behaved. Though she's kept on a long, sturdy chainlink leash (and she's not so trusting of strangers), she's still shockingly tame for a wild animal. She seems to listen to Ezekiel's commands and is happy to sit by his throne; even other members of the Kingdom don't appear to be terribly scared of her. That's due to the long history she has with Ezekiel, which is explored on the show and in the comics. Before the world became overrun with the undead, Ezekiel was a zookeeper. And Shiva was one of the animals he looked after.
In both the comics and the show, Ezekiel and Shiva's relationship has the same point of origin. She was born in captivity, and he had cared for her since birth. One day she fell into an empty concrete moat in her exhibit and ripped her leg open badly; though vets were on their way, Ezekiel risked his own life to ease her suffering. He saved her, and she was loyal to him from then on.
After the zombie outbreak occurred, he rescued her once again. Shiva has had his back ever since, acting as something between a pet and a guard dog (guard tiger?); in the comics, she even aids him in battle. However, one rule holds true: animals don't make it very far in The Walking Dead. In the comics, Shiva ends up sacrificing herself to a zombie horde just so Ezekiel can escape. She saves him in return.
Shiva serves a few different purposes in Ezekiel's life. She's a totally badass accessory that gives him major street cred and builds up his legendary status as a king-like figure in his community. But there's a lot more to it than that; Ezekiel cites Shiva as the last thing he loves in the world. Though she may potentially give her life for his, it seems she's already saving him in the way only a pet can: making the world a little bit more bearable just by being there.