Clix was the breakthrough they were looking for. A group of warlocks had been trying for years, decades, to find a vessel for their Old God to come into being. They went through countless sacrifices of every race, every alignment, and realized that they weren't able to perform their ritual on someone who already had a consciousness, or a purpose.
So they decided to make one.
One test after another proved unsuccessful, uncontrollable, or unreliable. They ceaselessly made changes and alterations to the formula, until test 159.
In the past, they were able to create a humanoid form, a voice, a brain, and a working body. This test was supposed to implement a mind capable of thought into the creature, in order to test the psionic capabilities of the Old God before completing the vessel in full. As such, much of the body wasn't fully developed, with arms and legs being transparent and glowing a light coral color. The experiment was going well, until the warlocks' past finally caught up to them.
The lab they were conducting these tests in was broken into and ransacked by the crown guard, finally able to have tracked them down after the numerous disappearances in the area. The warlocks were slain and the lab was placed under quarantine until the royal wizards could identify what was being done there.
And then Clix awoke. The mind they were given scanned the room, identified the slaughter that took place, and realized they weren't safe, so they ran.
The world was strange. And bright, until it wasn't, then it got bright again.
They learn about people, and animals, and color, and food, and all the rest of that stuff. They can communicate and move things with their mind, which scares people. They didn't much like the reactions from scaring people, so they retreated to the snow, where they got conscripted into the current adventure.
Clix has completely black eyes with pinkish-red pupils framed by a completely pale, white face and hair with no blemishes or wrinkles. They wear an expression of almost constant curiosity, as if they're experiencing everything for the first time. The cold bothers them, so they are almost constantly bundled up. Their arms and legs are transparent; you can see the bones inside (think Melinoe from Hades 2) and they glow the same pinkish-red as their pupils.