Character Name: Regulus Arcturus Black
Age/Birthday: Born: 1961. Died: 1979. Technically, he's 18 / 19.
House Affiliation: Slytherin.
Other Affiliation(s): Death Eaters, House of Black, Slytherin Quidditch Team
Family: Mother: Walburga Black; Father: Orion Black; Older Brother: Sirius Black. Cousins: Bellatrix Lestrange, Narcissa Malfoy, Andromeda Tonks. I believe he also has some connection to the Weasleys. Second cousins, or something.
Blood Ancestry: House of Black. Oh wait. Pureblood.
Physical Description: Regulus stands about medium height with a slim build and piercing eyes. He isn't overly muscular, but he is hardly weak either. He carries himself shoulders up, almost always with a smirk, and forever aware of his surroundings. He has messy black hair, and green / grey eyes.
Personality // Mental State: Before his death, Regulus would have been the favourite - and at times, only - son in the Black family. His older brother was a bit of a disappointment to his parents, and it fell on his shoulders to uphold the Black legacy. This was at times both a blessing and a curse for Regulus. The rewards were plentiful - high status in the wizarding community, more money than he could ever hope to need, just about anything he could want - but the burden was heavy. The things that were expected of him cannot have been easy to achieve, but it seems that Regulus was more than capable of it.
He was - of course - pulled into the darker side of the war. Whether this was a choice he made or something that was forced upon him is unclear, but it was likely the former. What we do know is that Regulus soon found himself in over his head. He didn't agree or like the way Voldemort and the other Death Eaters accomplished their goals, and treated others. The final straw came when Voldemort asked him to give up a house elf that he had a soft spot for - Kreacher. Voldemort used the elf to plant one of his horcruxes, and though he left the elf to die, Regulus went against orders and brought Kreacher back, questioning him on what happened. Through his own merits, Regulus filled in the blanks about what had happened, and created a false horcrux for Voldemort to find. If he was going out, he was going out in style.
Fortunatey - or unfortunately, depending on how you look at it - Voldemort and the other Death Eaters never leanred of Regulus' brilliance and betrayal. It was assumed by many that he had merely fled. This will be a great surprise and annoyance to Regulus upon his return, but he may not be very open about it.
Strengths: Regulus is clever - though not as clever as he gives himself credit for - with a solid conscience. He does know the difference between right and wrong, which is a great asset to him. He is quick thinking and logical, as well as being particularly crafty. He also has great confidence in himself and his abilities.
Weaknesses: Regulus is not much of a forward thinker, and tends to go too far with his actions before stopping to take stock of the situation. By this point, it is sometimes too late to take a different path - though to his credit, he seems to attempt to as well. This is somewhat self-destructive of him. In addition to that, he does not give people a lot of credit, even when it's due - people need to prove themselves to him. Since he is Regulus Black he is by default better than everyone else.
Magical Specialities: Regulus was likely skilled in Potions - I am basing this on his desire to live up to the expectations placed on him, and Slughorn's - professor of Potions at the time of his schooling - tendency to be drawn to students of high social and economic standing. Regulus would likely have been a favourite of his during school, and that would have encouraged him to do well in his classes. Beyond that, he may have had some skill in Care of Magical Creatures, as expressed by his affection for the house elf, Kreacher, and Defence Against the Dark Arts because of his family heritage.
Role in War: Regulus played a role in the war that was behind the scene. In addition to being a 'generic Death Eater', it was his house elf who hid one of Voldemort's horcruxes. Through sheer determination and a newfound will to bring down the Dark Lord
Current Political Affiliation: Undecided. Canon is clear about Regulus' change of heart in bringing down the Dark Lord, but he did join the Death Eaters in the first place, which leads me to believe that he is not a friend to Muggles. At the same time, he doesn't strike me as one to make the same mistake twice. He'll likely spend a great deal of time straddling the fence, but ultimately he'll be drawn to the side that offers him the most power - be that Lucius Malfoy, or Kingsley Shaklebolt.
That said, I highly doubt that he'd be against pretending to be on one side or the other. *wink*