The first thing that Nyx’s parents noticed when he was born was his completely black eyes. Normally this wouldn’t be a problem, since this kind of mutation is commonplace in House Aureus, but after a week it became clear that Nyx was actually blind. His parents were ashamed that they had made an “imperfect” child, so they told everyone else in the family that he had died suddenly.
Meanwhile, they kept Nyx carefully locked away in their manor, out of sight of any guests that might come calling, until he turned 15. They came into contact with a Rogue Trader who was on his way to the farthest corners of space and needed a navigator for the voyage. Nyx was initially excited to be out of his parents’ house, but then he learned that they’d essentially sold him to the Rogue Trader.
On board the rogue trader’s ship Nyx was treated little better than a slave. It was the ship’s crew that coined the nickname “Nyx”, in reference to his black eyes, and probably a play on the word “nix”, meaning “nothing”. Nyx eventually adopted the nickname as his own and thereafter refused to answer to his given name in an effort to distance himself from his parents and family.
(Nyx was eventually absorbed into Emir and Sigmund’s crew as a navigator after the two ships got into…a tussle.)
Nyx generally keeps to himself during travel, but he gets uncharacteristically excited if he’s given the chance to explore a new planet. He generally won’t say much unless directly spoken to, and it may sometimes be difficult to get an opinion out of him beyond “Sure, if you say so.”