A planet somewhere in the universe. There were creatures called tangled tails, which had tails stretch and shrink synchronously between them. For example, when one shrinks his tail, his brother's tail also shrinks simultaneously, and vice versa, with no delay.
Millions years later, a two-legged creature appeared, who used tools like human, and spread across the planet. Soon they found tangled tails and domesticated them to utilize their tails.
This is a work of science/speculative fiction of civilization, communication, and symbology on such environment.