Spoiler-tagged his background, as I, uh... wrote a lot... >.>
Light-skinned and very lean. He's not weak by any measure, but is certainly more built for acrobatics than weight lifting. He has a pair of pointed horns at the top of his head that he is often covering with hats or a hood, and wears baggy pants to conceal his demon tail. He does not seem to have sprouted wings, perhaps a "late bloomer". This never bothered him until his time in Hell, where it was evidently a point of mockery.
Music, primarily heavy metal and rhythm guitar, are his primary loves. He also enjoys reading, and is very curious about "fiction".
He has grown to dislike other incubi, and very much dislikes demon culture altogether. Being of a more humble nature, he cares little for the conceit of others, and demons are awfully conceited. What he despises more than anything, however, are boundaries.
Background: Phenex was born to a demon Anthropologist, or that is the best she can be described, in 1914. Due to the slow aging process of demon children, he has no memory of his life pre-1930's, and the time between the 30's and 50's are awfully fuzzy. He very much recalls having several different sets of fathers, all of which aged much faster than he had. Well, all except for Papa Buford, who struck him with a belt. That was during the... 60's? His mother took him into the bedroom for some "Patty Cake", which normally made Buford happy, but this time... he screamed an awful lot, and afterwards was nothing but ash. His mother seemed incredibly satisfied and had to lay down on the couch for a while.
It was only later that Phenex was made aware of what had happened. By the late 70's and early 80's Phenex was asking questions, such as why he had multiple fathers and they each aged so much, and why he had horns and a tail like mom but they didn't. He knew about Incubi and Succubi, of course. His mother educated him quite thoroughly on the demon realms and Hell since the 50's, but it didn't inform him of everything. In fact, he wasn't aware why she was always gone for such lengths of time, leaving Phenex to the care of her current lovers. She had to explain to him what humans were, that Incubi and Succubi relied on them to survive, and that his mother was spending centuries studying the ever-changing cultures and nature of humans. For this reason, they lived away from other demons, but had to keep Phenex hidden at a remote cabin for his safety.
By the 90's, Phenex was old enough to become antsy. He didn't always have a guardian watching over him, as he was old enough to watch himself. His mother had placed wards around the cabin to ensure no one could get in... or out, limiting how far Phenex could explore. Suffering almost a century of cabin fever and very bored of the self-congratulatory texts of Demon history, Phenex began to explore in and around the house... and found a smaller cabin that belonged to his mother, locked. It took him a while, but he figured out how to unlock it, sneak in and read the many tomes hidden within what turned out to be his mother's private office. He got in trouble the first time, having left plenty of evidence behind, but he broke in repeatedly, taking extra measure to keep everything as it had been. He read about human culture, but he could find no real "starting point". It was a mess trying to figure out their histories, which culture was what, which God they were praying to, and so many other changes and evolutions in what felt like such short spans of time. He got in trouble plenty of times for breaking in, never as sneaky as he believed, and each time his mother became more and more secure.
So finally, in the mid-aughts, Phenex began to research the ward instead. He finally one day broke it, and left to wander human society. He knew enough that he hid his horns and tail, at least, based on his "fathers". However, he wasn't prepared for the cars in the busy streets, or the sheer volume of people, or the noise. He stumbled upon a library after seeking a silent place, using the opportunity to try and find more books on humans. What he found was even more confusing. Books that seemed to contradict belief systems, facts about time periods, and even record events that hadn't happened yet. Little did he know that Phenex discovered "fiction", a concept his mother or fathers had never introduced him to. Fascinated, he chose to wander and find a place where he could sit and watch people. Most eateries and trade locations did not seem to like having a teenager standing around and watching, but he finally found the Mall, a public space filled with people of all kinds. After exploring many stores (and getting many uncomfortable stares as he wandered the women's lingerie store), he stumbled upon the music section. His mother had shared music before, most of it classical, much of it Jazz and Lounge singing, always slow on the uptake of new music. He put on the headphones, sampling different CD's, until finally he stumbled upon something that sounded... incredible to his ears. Mercenary, they were called. Energetic, filled with angry emotion, sadness, melancholy, bittersweet, with percussion and strings that just made you want to jump around, a fusion of singing and screaming that felt... cathartic.
Unfortunately, Phenex was unfamiliar with currency, so as he tried to walk out of the store with the CD's, not even sure how they worked, just that they stored music, he was called out and chased down by security. Enforcement got in touch with his mother, luckily not finding his ears or tail stuffed in his clothing, and after spending a night in the juvenile detention facilities he was reunited with his mother, worried sick. The time home was spent with much lecturing, though he remained silent. After several days of silent sulking, his mother returned with a gift. She had purchased the CD's he tried to stole, as well as purchasing a CD player.
While this helped a bit, he still felt disgusted with his cabin fever. After several more break out attempts, none of them successful, his mother finally decided in 2010 that she had to leave him with family in Hell. She at least cushioned the blow with still more CD's and even purchased a guitar for him to play. Without any proper guidelines, however, he has been forced to learn the hard way, and is nowhere near as good as he ought to be. When he tried to reach out and speak with other Demons, he discovered that they all had a ridiculous hierarchy. There was no sign of the jovality he had witnessed in that library, the mall, or the many locations he scouted. It was all based on who was "best", and who was "best" was often based off the reputations of parents.
As such, Phenex continued his life as a loner. He was also beginning to feel "the hunger", and while he was occasionally able to satiate it temporarily, it was often with less savory demons. Other succubi seemed to actively avoid him, or at least in their territory When his mother informed him he'd be returning to the human world, he was ecstatic. When it was for the Academy of Succubi and Incubi, though, he was disappointed. He wouldn't be stuck in a cabin, true, but he'd still be stuck in a regimented community filled with conceited beasts that lived their lives according to rigid boundaries.
At least he could bring his guitar, and at least he could finally truly feed this blasted hunger growing within him.