He is the younger brother of Allen Smith, aka, "Al(x)ne".
About the two brothers:
Born in raised in Boston, Mass, the Smith brothers were middle class kids who lived typical lives. Then Allen discovered he had a strong business sense and came to own his very own store by the time he was 25. Over the course of the remainder of his twenties and well into his thirties, he became a successful land owner and rented out his properties to various parties to either reside or do business from. He was also a ruthless business back then, and did many less than morals things to get what he wanted. I think a few people ended up wearing cement shoes, in fact.
When he was 37, in 1990, The Black King showed Himself to him and the two made a deal in exchange for Allen's life. He would buy properties that The Slender Man could who was places to hide his followers or victims.
Over time, Allen became even more corrupt as wanting to save his own skin overcame any guilt he may have once had, and eventually became a powerful Agent in The Black King's ranks.
In fact, Allen was already the head of all slendering operations in Mass, when I moved to Boston to take up my post there, in 2000.
Allen's younger, less intelligent but more physically adept, brother. Bruce played sports in high school and college, eventually joined the military and was trained as a sniper.
Whatever he did during his time with the armed forces either deranged him or awakened his bloodlust. All I know is that when he left, he still craved more blood and killing. He became a successful serial killer before he was approached by both The Black King and his older brother. Now holding the position of being Allen's personal assassin, he could kill as much as he desired and then some...and did.
He's as insane, sadistic, and ruthless as MorningStar, as dangerous and well-trained as any member of Nightcrawler's crew, has the power to enter and exit any sub-dimension he wishes (and take anyone he has with him there as well), and he has a bone to pick with:
with me being the first target before he moves onto anyone else.
As long as I live, he will not come after any of you. I know how he operates. He'll torment me relentlessly until I can run from him no more, and then he will torture me to death in ways far worse than what Allen did to Clyde. Then he'll do the same to whoever comes next.
Gentlemen, I'm not going to lie. The situation for all five of us is bleak unless one of us kills him. On one hand, he is a powerful Agent and a combat expert. On the other...he is still human and very killable.
Perhaps I should seek out the Observe and Terminate crew for assistance.
He stands at 6'2'', has matching brown eyes and hair, and a broad frame. He had a scar reaching from far above his hairline on the left down, across his entire face heading down to his right shoulders. Other facial markings include two claw marks above his left eye, and a Operator symbol carved into his left cheek.