Asceticism in India. An ancient tradition of suffering inhumane discomforts for "spiritual purposes", some schools of yoga for example believe to this day that by holding their bodies in uncomfortable positions one relieves the rest of his village from pains and all evil things, thus such people are chosen at an early age and their austerities are encouraged. They are seen as saints who absorb the suffering of the rest of the village, and they're worshiped on the same level as deities. It is also believed that through his austerities a saint gains incredible spiritual powers and access to the infinite wisdoms of the universe and thus can serve the people even more by being some sort of an oracle.
Sleeping on a bed of nails is one of the world famous Indian austerities but there's a lot of less common ones. Saints begin their career since childhood when it's easier to teach the body to do something that makes people cringe and looks bad enough to make people start worshiping you as a divine being. At a certain time children of the village line up to be examined by a guru who chooses only one, the blessed one, who has specific conditions that only the guru can discriminate.
But younger saints normally practice inside caves or in far away places with their guru, so this twisted boy hanging on a branch dangerously high above the ground was quite a rare sight. The boy was so deep in stasis that even breathing could not be seen, his body only swayed a little to the wind.
The nearby village had some information on the boy. His name was lost and people called him Mowgli after the famous feral kid. When the boy was five, his guru came to his parents and convinced them that the boy was a minor incarnation of the serpent god, and as a proof the guru bent the boy in various ways that convinced the parents and they let their son be educated at the guru's ashram. Since then the guru would hold the boy in the most extreme positions for very long periods of time until the boy gained the flexibility of a snake and even a little following of worshipers who would provide food and money in exchange for witnessing the divine wonders.