He had grown up with stories about the Fae and how dangerous deals can be to humans. But as a child, he was fascinated with stories about characters who find their other half and live happily ever after. And at six years old, he decided to sneak out of the house and into the untouched wilderness to make a deal. No thought of the consequences.
Traditionally, one just needs to bleed in the heart of the woods to make a deal. The heart of a mountain or tide works as well, but he decided that that the best place to make a deal would be where the three intersected. He didn't think about why the paranormal didn't go near that place, or how odd it was that none descended upon a wandering child.
He had walked for hours when he stumbled upon the perfect spot for his deal. It was a short cliff side, the forest turning into mountain as the high tide brings in water. It was a beautiful scene, not the spot one thinks of when a horrible mistake is made. But it was, and as he cut into his flesh the childish wish for he other half was made. Someone who completes him, who would still love him even after they fight, who would stand by him even if the world was their enemy. And so it was.
The different planes brought forth different body parts, and with inexperienced hands,he starts to sew together his half. Dark blood had soaked his sleeves and shorts, staining his skin but not the needle as bright red thread connected each piece. As the sun started to set and the stars appeared, all that was left was to give the newly made boy eyes. With a pebble from the mountain, smooth by tide water, and the iris made by bright red flowers, he add another drop of blood for a pupil. But the human boy didn't placed both eyes into the vessel, no he instead ripped out his right eye to share with his other half. So that they may mirror each other and always be together. And as the boy fell unconscious, the mirror woke up.