Tiger is the main antagonist of Anansi Boys by Neil Gaiman. He is the Cat God, representing all the ferocious, wild Cats of the world, but representing Tigers most of all. He is the arch-nemesis of Anansi the Spider God, who has humiliated him many times, in front of the other gods, and thus Tiger has sworn to kill Anansi or his offspring.
Tiger and Anansi lived in pre-historical Africa, where Anansi was considered the village idiot and Tiger was considered a noble and majestic hunter, although evil and vicious. The pranks Anansi played on him were many, but one went too far. Anansi's grandmother died one day, and so he wheeled her into town to bury her, and on the way stopped for some beer in the heat of the day. The innkeeper came out and offered Anansi's dead gran some beer, and she farted loudly, as the dead sometimes do. The innkeeper thought this was a great insult and began beating her, and in the end she rolled off the wagon and didn't move. So Anansi came rushing out and yelled at the innkeeper for killing his grandmother, so the shocked innkeeper quickly gave Anansi some fruit and coins, to keep him quiet.
The next day, Tiger was passing Anansi's house and he smelled all the food and saw the money, so he became greedy and asked Anansi where he had obtained all this from. Anansi said he could never lie to Tiger so he told him about his grandmother's death and how he had gone to a pub and got the money from the innkeeper. So Tiger decided to kill his own grandmother, despite Anansi's having died naturally, and Tiger killed her and took her corpse into town, shouting "Who wants a dead grandmother?" This made him the village idiot and everyone jeered and ridiculed him and Tiger ran off, vowing revenge.
Another time, Anansi and Tiger decided to go swimming, and Anansi saw Tiger's balls, mighty fine balls they were too. So Anansi asks Tiger if he can guard his balls while Tiger swims, and Tiger gives the Spider God his balls. When Tiger is swimming, though, Anansi goes into town and boasts about having Tiger's grand balls, and thus all the monkeys love this story and begin spreading it far and wide. Tiger comes back and hears the gossip, and asks Anansi what they're laughing about. Anansi says he had Tiger's balls. When Tiger sees the laughing monkeys he roars at them in anger and chases them up some trees, and to this day monkeys stay in the trees, hiding from Tiger's ire.
Anansi had sons later in life, and then he died. (Or, rather, pretended to die.) Anansi's death made his son, Charlie Nancy, wonder about his family, upon which he heard about his estranged brother, Spider, who was also a God, from a witch. So, Charlie entered the realm of the gods, which was the Beginning of the World, (although it looked more like the End of the World) and then Charlie saw all the Animal Gods, who turned him away, all holding grudges against Anansi, even though Anansi was "dead." The only gods who would talk to Charlie were Monkey and Tiger. Tiger explained how much he hated Anansi and any of his kin. Charlie was frightened of Tiger and eventually met the Bird Woman, who was the only god who held no grudge against Anansi and decided to banish the intrusive Spider from Charlie's life.
The Bird Woman told Tiger about this deal, and she captured Spider, and left him strung up on a beach where Tiger would come and eat him. Tiger appeared in vaguely human form and chatted with Spider, offering him meat, which turned out to be a raw caracass infested with maggots. Realizing this, Spider threw away the meat and Tiger ran away, sometimes looking bestial, sometimes human. That night, Tiger returned and began to stalk Spider. Spider broke out of his trap and summoned his Spider Army, which attacked Tiger and bereaved and injured him. The beast ran off and swore revenge again.
Back on Earth, Charlie's boss, Grahame Coats, had captured his fiancee, Rosie, and her mother, and imprisoned them in his Caribbean villa. So, Grahame Coats came down to kill Rosie, and was injured by her mother, and both women escaped. Tiger appeared in the cellar, and possessed Grahame. Using Grahame's body, Tiger made his way upstairs and attacked Rosie, and her mother, but was ultimately thrown from Grahame by the ghost of a woman he had murdered. Grahame Coats' soul was reduced to a stoat, and imprisoned in the Beginning of the World in some cave.
When Charlie and Spider reunited and made amends, they went to the Beginning of the World to restore what had been before. Anansi was also there, having slipped to that place upon his "death". Emboldened by seeing his father, Charlie began to sing, and all the gods approved of his singing, as he was singing for Rosie's mother to be healed from her coma, which she was. Tiger came up and growled that the songs weren't Anansi's, and all stories should belong to Tiger. But before Anansi came along the world was dark and savage, and the hunt was all that mattered, and not wanting this, Charlie made fun of Tiger, ridiculing him, and all the gods began laughing at Tiger, forcing him to run into a cave to confront his anger. Spider made the cave collapse on the entrance, imprisoning Tiger for eternity.
In the cave, Tiger was confronted by Grahame Coats' soul, who was now a stoat. He also made fun of Tiger, so Tiger silenced him by biting his head off.
As the Cat God, Tiger had numerous powers, such as possession, immortality, and omnisicence and omnipotence. He wasn't invulnerable, though, as he was injured by Spider's Spider Army. He also had the ability to bear curses, as he cursed Anansi's line.