Polo must have had a mother and a father, once. His sister told him they died when he was born, leaving by his side the last vestiges of the souls they had stolen, for him to eat when he woke. They left him nothing else—no home, nothing to remember them by. They didn't even name him properly.
After that, it was just him and his sister, for as far back as he could remember. Together, they lurked unseen in the woods, and they were always starving. Those woods were traveled by very few, and those that did come their way did not give up their souls easily.
For all that time, Polo didn't have a name. "You only get one chance at choosing a true name," his sister told him. "You need to wait until you figure out something that's right for you. Something that can gain you souls." She wiggled her horns in frustration. "It is very difficult to convince the mortals to say 'Antidisestablishmentarianism', and even harder to get them to pronounce it correctly. I wish Mother and Father had chosen something shorter for me."
"But it's a very pretty name," the creature who would one day be Polo told his sister. "It suits you."
"Yes, but I'm starving," Antidisestablishmentarianism said.
Polo-that-would-be was starving too, but he didn't say anything to complain. At least she was able to bring in souls once in a while; until he was able to feed them as well, he didn't think it was his right to say a word against her.
He wondered what it must be like, to dip your shadowy appendages into a fresh, warm human soul, not just to gnaw on the cold remnants that Antidisestablishmentarianism brought home. To raise a still-throbbing soul to your bony snout and suck at it. To touch a truly living being, flushed with its own mortality.
Sometimes he even wondered what it would be like to be mortal, to be one of them. His own kind could waste away into nothing when they went too long without feeding. His sister called that death, but was it really? They grew no colder than they had been already; there was no moment when the soul left the body since they had no soul to begin with.
Then one day, finally, Antidisestablishmentarianism returned to their home in the deepest part of the forest after her longest absence yet. She set a few dried crumbs of soul on the boulder where they stored such things, and she tipped her horns at her brother. "I've found a wonderful name for you," she said. She wrapped her shadowy appendages around him formally, and even though neither of them could feel the contact, Polo imagined that he felt the tiniest bit warmer in her embrace. Stentoriously, she spoke the words over him: "Your name is Polo."
"Polo." Polo tried out the two syllables. "It's rather...short."
"Yes, but it's the most marvelous name I've ever found," Antidisestablishmentarianism said, eyes glowing with excitement. "I found one of the mortals' assemblies of knowledge. They call it a library. I looked through all of the records they had assembled there, and in one I found a mortal ritual recorded. The ritualistic call which you have to speak is 'Marco', and the ritualistic response which they must say in return is 'Polo'. It's wonderful!"
Polo clashed his horns against hers, since that was the only part of their bodies corporeal enough to touch. "You're right, it's wonderful," he said. "I think it's my turn to go hunting, then."
Antidisestablishmentarianism clashed her horns against his in return. "Good hunting, brother," she said.
Polo crept through the forest. He'd never been so far away from his home before. The trees—as soulless as he, though perhaps slightly more alive—made no reaction as he slipped between them. The wind was blowing somewhere above, and it, too, was soulless. Polo wondered how far he would have to go to find a soul. The miles seemed endless, and still the forest stretched on.
Then it was there. A golden glow between the trees. A soul! Polo could almost taste it, it felt so warm even at this distance. He crept closer. He wondered if the mortal would mind if he touched its soul before it gave it to him. Antidisestablishmentarianism had advised him against it, saying the mortals were harder to convince if you'd already been poking at them, but then she'd been at a disadvantage: there were no sacred ritualistic calls about Antidisestablishmentarianism. And the soul looked so inviting. He'd never touched a soul that was still alive before. Without barely thinking about it, he found himself moving closer and closer, shadowy appendages outstretched.
But this was his first hunting trip, and he shouldn't take unnecessary chances now. He forced himself to stop, wrapping his ephemeral body around one of the trees. "Marco," he called. Antidisestablishmentarianism was going to be so proud of him.
"Yeah?" the mortal replied.
"What?" Polo exclaimed. He cast back in his mind—no, Antidisestablishmentarianism had definitely told him his name was 'Polo', not 'Yeah'. What had gone wrong with the ritual?
"What?" was the mortal's next response, and Polo couldn't understand how this had all gone so terribly wrong when his sister had told him how simple it would be.
Polo stumbled through an explanation of the ritual as his sister had explained it to him, and the mortal explained in return that its name was Marco and that it definitely didn't want to give Polo its soul. In desperation, Polo reached out his shadowy appendages towards that golden, delicious soul, hoping that just a touch would make up for the taste he would never have. He was so hungry—he'd left at home all of the crumbs that Antidisestablishmentarianism had scavenged, thinking she would need them more than he. But the mortal's refusal was too strong, and Polo's appendages bounced off of the glow, leaving him just as cold as he had been before.
The mortal—Marco—walked away, and as it did, the glow faded until Polo was once again all alone in the soulless forest, huddled in a shadowy lump at the foot of a tree.
He would have to try again, eventually. He knew he must, because he couldn't let his sister down. But he could never take another true name. Polo was his name now for the rest of his life, just as Antidisestablishmentarianism was his sister's, and the mortals didn't seem very interested in repeating his name any more than they had hers. And he was so hungry. "Marco," he whispered quietly. "Marco."
But the soulless forest did not reply.