Overview
Kaa is a fictional character from The Jungle Book stories written by Rudyard Kipling. He is a giant snake who is 30 feet long.
In the books and many of the screen adaptations, Kaa is an ally of main protagonist Mowgli, acting as a friend and trusted mentor or father figure alongside Bagheera and Baloo. However, Disney's screen adaptations portray him as a secondary antagonist who attempts to eat Mowgli.
Kipling's Mowgli Stories
First introduced in the story "Kaa's Hunting" in The Jungle Book, Kaa is a huge and powerful snake, more than 100 years old and still in his prime. In "Kaa's Hunting", Bagheera and Baloo enlist Kaa's help to rescue Mowgli when the man-cub is kidnapped by Bandar-log (monkeys) and taken to an abandoned human city called the Cold Lairs. Kaa breaks down the wall of the building in which Mowgli is imprisoned and uses his serpentine hypnosis to draw the monkeys toward his waiting jaws. Bagheera and Baloo are also hypnotized, but Mowgli is immune because he is human and breaks the spell on his friends.
In The Second Jungle Book, Kaa appears in the first half of the story "The King's Ankus". After Kaa and Mowgli spend some time relaxing, bathing and wrestling, Kaa persuades Mowgli to visit a treasure chamber guarded by an old cobra beneath the same Cold Lairs. The cobra tries to kill Mowgli but its venom has dried up. Mowgli takes a jeweled item away as a souvenir, not realizing the trouble it will cause them, and Kaa departs.
From Wikipedia (CC BY-SA 4.0).