It had two sets of wings much like a thunder bird that were folded against it's body at the moment and four clawed bird feet that gave the form a griffin like feel. That was where the avian features ended however as it had a long serpentine tail at the end of it's body covered in feathers but ending in a familiar circular metallic ring. It also had a short neck that ended in a basilisk like head that included the sharp horns except that it's mouth had a beak at the end. It was honestly one of the most eerily beautiful creatures Nick had ever seen.-
It was only the size of a housecat though so it wasn't very intimidating at all and Nick had no idea how big it was going to get. "CHIRP!" Nazgul trilled happily as it started walking around clumsily clearly not used to it's new form. "How in Merlin's saggy beard am I supposed to explain you?" Nick asked out loud while looking at the clumsy creature. Nazgul quirked it's head adorably at the question in confusion before ignoring Nick. He was at a loss as to what to do however since he couldn't exactly hide Nazgul away due to his familiar bond to it.-
Unlike owning an owl or cat in which case they could be away from their owners for long periods of time and true familiar bond like that which Nick had with Nazgul meant it would be very bad for it's health to be separated from him. This was also the reason that Fawkes is usually never far from Dumbledore for very long. When Nick willingly gave Nazgul his energy to complete it's transformation he had been familiar bonded to it and now they were bound together on a spiritual level.-
Nick could only sigh and seal up Slytherin's library for later use since this took priority. Once the library was sealed he walked over to the newborn and scooped it up into his hands. Nazgul didn't resist but rather snuggled up with a yawn and immediately went to sleep with it's tail wrapped around Nicks arm. Dusk who was flying about the chamber outside the statues mouth landed on the ground near Nick but was shivering in fear as it looked at Nazgul. It took Nick a few seconds to realize why Dusk was terrified of Nazgul.-
See each of the immortal bird species would always be reborn after they died either from old age or from being killed. However if Nazgul still possessed the ability to devour souls then there would be nothing to be reborn should it kill an immortal bird as that immortal bird would lose it's very soul. Such a thing was likely instinctively terrifying as far as an immortal bird like Dusk was concerned. At this point Nazgul may as well embody the truest form of death possible , soul death. "Calm down mate , she won't hurt you I promise." Nick said reassuringly and Dusk relaxed a little but still refused to get near Nazgul at all.-
Helpless Nick could only leave the chamber of secrets with Dusk following behind at a distance. As it turned out it required yet another few miles of walking on the long pipes wall to get out again. Moaning Myrtle took one look at Nazgul in Nick's arms and noped out of the bathroom immediately. Dusk immediately flew away once they left the chamber entirely , likely in an attempt to put as much distance between him and the sleeping Nazgul as possible without leaving the castle.-
Nick got more than a few of his fellow students(mostly girls) approach him to pet Nazgul who didn't seem to mind the attention at all while Nick himself was mentally sweating buckets. The small soft adorable creature in his arms could kill souls so if she decided she didn't like a particular student for whatever reason ..... yeah bad stuff. Still despite waking up mid transit to Dumbledore's office Nazgul seemed perfectly content to get carried around and petted like a pampered cat. Still Nick made it to the gargoyle statue of the headmasters office without any issue "sherbet lemon" he spoke and the statue moved aside.-
Dumbledore was surprised to see Nick so spontaneously but moment Fawkes saw Nazgul he stiffened in fear which the old wizard noticed through his bond with the bird. To his surprise the elder wand in his sleeve also seemed terrified of the creature being held in one of his students arms. "I feel like you have quite the story to tell me in regards to that creature you are holding." the old wizard said with a small chuckle to try and hide the uneasiness he felt at the fear that those two extremely powerful things held towards whatever that creature was.