Nox is described as a moderately handsome young man with black hair and grey eyes. He is tall and lean, but not gangly.
Nox Owen is friendly and respectful to Celaena during their time in the King's Champion Tournament, befriending her.
Nox made a name for himself at an early age, rising up from one of the countless city orphans to become one of the most talented thieves in Terrasen. After Adarlan’s conquest, Nox turned his talents toward tormenting Perranth’s new rulers (viceroys and generals sent in from Adarlan), and has been rumuored to occasionally see to it that those stolen goods make their way into the hands of Terrasen’s rebels. He was sponsored in the king’s competition by the new Minister of Terrasen (a native himself, and was granted immunity if he lost. His motives for accepting the Minister’s offer, however, remain unknown.
In the first novel, Nox was one of the few candidates who are actually friendly towards Celaena. The two in fact became friends and had helped each other numerously throughout the course of the tournament. After the number of unsolved murders in the castle increased, Celaena adviced Nox to flee Rifthold before he becomes the next victim. Nox heeded her advice and fled Rifthold, and his fate thereafter remains unknown.
Nox is seen as a messenger, not employed, of Darrow.
During a meeting of the Lords of Terrasen and commanders, Nox enters with another person that ended up being a Valg that found out that Aelin -Lysandra- was a shifter and then was killed.
Nox apologized with them and left the tent.
While Aelin (Lysandra) was going to her tent after talking to Aedion, Nox fell in step beside her and told her that he knew she wasn´t the real Aelin. When she asked her why, he asked if she recognized him and she said that he was a messenger, then he told her that he was a friend of Celaena when she was at the Glass Castle .