Ferocity
Don't own any of it.
INSPIRED BY THE SONG "SUICIDE BY STAR" BY GOD IS AN ASTRONAUT
Grimmjow would never, ever forgive that bastard Aizen for making his life a living hell. Yes, he had given him a purpose in life and he loved fighting more than anything but the irony in the situation was that he hated Aizen for maki him a slave but all the while giving him something to cling to. He would have liked to think that spending all that time fighting with his claws and teeth would have made him as fierce and dangerous as he was (they certainly did contribute to it) but really, what had made him fierce of all was the pure hatred and rage he held for Aizen.
He constantly had a war waging within the depths of his mind and heart. His entire existence was a love/hate, bitter sweet, contradiction. He desperately wanted to say that he was on his own and wanted to rise up to become king but his pride consumed him and he couldn't admit that he was weaker than his creator.
He always found it funny how thugs worked. He discovered that within itself, Aizen giving him a purpose was a purpose or cause in itself. He would destroy anyone or anything that stood in his way and he would slaughter anyone who had the guts an lacked the brain to look down on him.
Before Aizen actually took him in, he was the ring leader of his group. But as he entered the kingdom Aizen had built himself, he realized the pecking order had changed. He was infuriated. He absolutely hated the thought of someone "owning" him, or at least thinking they did.
He labeled himself an outcast. Not only did he hate Aizen but he hate the others for showing weakness by following Aizen and not asking any questions. He viewed them as weak and pathetic. Nobody could tell the king of the jungle who was boss.
Even the slightest hint of a condescending tone could set him aflame, like that Kurosaki kid. Who the he'll did he think he was anyway? Grimmjow always thought of him as an annoying pest, better yet, a rodent. He knew nothing of real pain and anger and hate. And yet his eyes looked at him with that damned look! That look of wisdom and kindness. He HATED that look.
After his battle with the rodent, he found himself in the desert o Hueco Mundo, bleeding out. He couldn't let this happen. He was a king, not a man to be left forgotten or even worse, remembered as weak and dying an dishonorable death; bleeding out in the middle of nowhere. A shinigami had found him and as much as he struggled, she had healed him as little a possible. She must have sensed his hurt ego. So now he had another thing to be pissed off about, big surprise.
Now, three years later, he still counted his scars and cursed all the names of people who were already long gone, all being killed in battle, damning them all the same. He wouldn't forgive any of them for the bullshit they fed him previously.
He had exiled himself to the very outskirts of Hueco Mundo. Surprisinly, so had many others. All the people the Kurosaki brat didn't have the guts to kill, and some people who were just damn lucky, like Nel. He spent alot of his time with her, most of it being training. She was there when he first became an Arrancar. In fact, she was the first person he saw when he was "born" (or given a more human-like form) shewas the only person in existence he had ever bothered to get semi close to. He never really cared for her child form and wouldn't ever admit it to anyone, hence him trying to "kill" her along with that Orihime girl.
It seemed that recently she has been able to control her phasing from her child form to her adult fir much better and with time, this had brought him some sort of patience. While he was still the same old enraged "Kill-anyone-who-looks-down-on-me" Grimmjow, he had changed a small amount. He could safely (but never would) say that she had helped alot in him gaining patience and being less of an asshole.
But, no matter what, he was still the howling and ferocious Panther he was made to be. His hatred and ferocity was wired into his system. This was Grimmjow's whole existence.