There is a strong eternal aspect to werewolf mating or pair-bonding. Wolves form a bond through a series of processes that are a combination of natural instinct, deep connections and ritual. There are two Marks, the first physical and highly visible. The First Marking is given on or near the full moon, though there are exceptions to this. The intervening time until the second full moon is a more intense courtship period. The Second Marking is a permanent, intangible link it is invisible, unlike the First Mark, but as instantly recognizable by any wolf.

...

Derek paced. It was a useless effort but he could not keep himself from it. Dust motes drifted into the air, displaced by his bare feet as he moved across the floorboards. He should be out doing something...anything, anything other than pacing uselessly. Yet he could not think of anything to do. Recent complications had surfaced and he was now more lost than he had been a few weeks before. His sister, one of the last surviving members of his family was now dead. Murdered at the hands of the alpha. Derek had wanted the alpha dead before simply for simplicity's sake. It was easier to make peace with the humans when humans weren't dying. But now, now it was a different story. He wanted the alpha to die slowly, painfully, at his hands. Maybe he would even cut the bastard in half. But thinking of the alpha only brought him back to his most recent problem. The alpha had left Jackson alive. It hardly conformed to the pattern he'd been making. So why? Why did the alpha let him live? It wasn't because Jackson was a sparkling example of humanity. It simply wasn't possible. He paced to the windowsill, clicking his fingernails against the wood as they extended and retracted. His mind was moving too fast to control it. He stopped suddenly, fingernails sinking into the wood. Derek did not move, hardly able to breathe. Ever so slowly his eyes swiveled down to his hand. It wasn't too long ago that he had run into Jackson in the hallway. And scratched him. Derek's jaw clenched unwillingly. One thought passed and destroyed all others. No.

Before the denial could pass his lips he knew it to be true. Why not? Everything about his life had been inconvenient. Why not this too? He placed his other hand carefully on the sill to hold himself up. Perhaps inconvenient was not the right word. This was downright lecherous. Hideous. Completely unbelievable. He'd never really thought about who he would mark or when he would mark them. If he ever marked anyone at all. Being a werewolf was not easy. Accepting that someone else was a werewolf could at times be even worse. Settling down had never really occurred to Derek. Not that he was going to settle down with Jackson. He shuddered at the thought. No, love had never entered the equation of his life. Now he only knew one thing. There would never be a second mark. There was no need for this to mean anything at all. He simply had to stay away from the infuriating boy. Everything would be fine. Not perfect...not even good. But with enough luck his life would return to acceptable.

A/N: If you know me at all you know I'm addicted to slash. Couldn't help myself. I won't strictly be following the show mythology (obviously) and I can't promise I'll even try to follow plot wise. No...this will mostly be my own creation.