WARNING: This would spoil you probably a little(?) for Kingdom Hearts: Dream Drop Distance and probably the rest of KH before that. Read on if you do not mind.

Pain.
Deceit.
Betrayal.
Loyalty.

Kingdom Hearts...where is my heart….?

"You don't have one," A whisper echoed around the darkness, a sudden chill that blanketed the void "But that does not mean you cannot receive one."
Light filtered into Saix's vision yet he could not feel the warmth nor taste the bliss of waking up from the black and rigid void. In fact, he felt as if he had never left it.

That's right. How could he feel, when he never had a heart to begin with?

Golden eyes watched him in silence as Saix rose to his feet, his fingers rested upon the mark on his forehead. What had happened?
Oh. That's right. Sora had defeated him…and he had faded…

Yet why was he here, standing at the very spot where he had lost…?

What happened after the time when he fell under Sora's keyblade? How much time had passed?
Did Kingdom Hearts come into completion?
Did Xemnas's plans worked?

Were they finally able to regain a heart?

No. It didn't felt so.
"Superior…?" He asked, turning towards Xemnas, who only watched on as he stumbled about.
"The tables have turned, Number VII," The nobody announced with a solemn tone "For you to once again be here means that you had proven your utmost loyalty to me and I congratulate you," He continued "And so, you qualify."

"...Qualify...but Kingdom Hearts….is it not completed yet?" He raised his voice in ragged confusion. However, his superior merely stared back.
"We have far more important matters to proceed with, number VII," Xemnas was rigid as he had always been.

Saix could only draw a sharp breath at his superior's answer. He was confused but it will eventually clear as he slowly regains himself again but what he felt now was quite similar to the times when he first became a nobody.
When he first became Saix.

"I will give you both a purpose."

They had lost their heart.

Lea….no, Axel stood up, his back faced against the bluenette, muttering his new name, testing it upon his lips.
"Lea…?" Saix reached out for his friend, someone whom he had been together for years. The name however, did not leave his tongue.
Axel turned back to Saix and mouthed his previous name, but found that he couldn't. "Isa...?" No, the words would not form. It had been stripped away, no longer is the name a privilege to them. Like their heart, it had been ripped, never to exist except in their memories.

"Saix," Axel called, a grin hung upon his lips as he reached a hand towards his 'friend' but it was fake, plastic. Saix saw the emptiness in his eyes, now a heartless entity that can only act upon past memories threaded into his existence.

It felt like a curse.

But it is now their being.
It is what made them special.

Weeks.

It wasn't long before Axel had the glint back in his eyes again and looked more alive as he should even as a nobody. Soon, there were more who would joine the organization. Saix treasured the fact that the redhead was still with him, even when they had both lost their most important part of their being. Yet he cannot help noticed that his friend was empty. He cannot help feeling like the whole thing was his own fault to begin with.

They aimed for Kingdom Hearts, a power that was believed to be able to restore their missing existence. Yet never did they show any progress even as they took on missions that their superior had given to them.

It wasn't until that fateful day, when he came back mindlessly trying to outwit his superior. It was Vexen that had planted the idea into him, that there could be even a glint of hope that a heart could be restored.
Saix was vain and reckless and so he seek out that power, not of Kingdom Hearts, yet hoping to regain his original self and the past Lea. But by doing so, he had betrayed the organization and that itself had set Xemnas to reveal his true side, a side one would know not to mess with.

Screams echoed around the room and the other members looked on in disbelief. The X that marked his face flow a crimson liquid, proving that even nobodies could bleed and could actually feel pain when being tortured.
"I'm sorry," The bluenette wept, clutching his bloodied face as he apologized. It was the first time someone dared betray Xemnas and of course, the head of the organization did not take it lightly. He had took it upon himself to even carved the mark of the organization unto Saix's face.
Saix was in pain and none of the others could help him. Axel in particular had to be held back by Laxeaus and Luxord, screaming for Xemnas to stop. Saix's pride had been stripped away, the last of him that was holding him together crippled and broken. He went on all fours before Xemnas in a hopeless attempt to quench his anger, despite his bleeding face and bruised body.

"I have great hopes for you, number VII," Xemnas whispered, hurling the bloodied carving knife aside. "Do not betray me again and let this be a warning to the rest of you," With that he left the room, leaving Axel to tend to Saix's wounds, which will later turn into a scar that will forever remind Saix who he should remain loyal to, who his real master, his 'superior' is.

Time passed.

"You've changed,"

Axel murmured, glaring at Saix who stared back with a frown.
"What?" Saix questioned.

"You've changed ever since that—that person gave you that scar!" Axel accused, shaking his friend's shoulders.
"If I had a heart, then this would be where I'd die laughing," The bluenette merely replied in a solemn tone "No, I merely adapted, Axel,"
"I merely decided to understand where I stood in this castle,"

It was a reply weaved by the cold and the chill that Saix had gained over the time that he spent as a nobody, void of all feelings, serving loyally to Xemnas. He had turned into the perfect tool for the organization.

"Now Axel," Saix pushed a file towards the other "Where do you stand?"

Axel hesitated, his brows flinching as he processed the whole situation. Finally, he snatched the file from Saix and proceeded through a portal, uttering the word "Fine," before throwing a rather pained look at Saix.

It was then that HE arrived.
Roxas, a boy who could control the keyblade. Thanks to him and the Fourteenth member, Organization XIII had finally started making progress, and soon, Kingdom Hearts was formed.

They were nearing their goal.

Even when half of the organization fell in Castle Oblivion, Saix was still confident that they could still proceed.

Until…

"Which would you suffer the loss of...?" Saix questioned, turning towards Axel "Some make believe friendship….or a real one?"
Axel was in distraught. He had lost almost everything and Saix could see that having Roxas gone had further plunged his friend into utter despair. Whatever one chose, there will always be a price to pay.

And paid Axel did. After running away from the organization, Axel had finally paid the price for his choices when he spent his whole being to protect Sora. Though far, Saix could feel his presence fading and silently, the proud nobody wept. An unworthy end for him, in Saix's opinion. Yet he felt pained.

It felt as if he had a heart again.

Kingdom Hearts….where is my heart?

Now.

The hood was drawn over his face. Now revived, he could not help admitting that he felt different, strange and it was unpleasant. He was rather surprised to see Sora sitting in the throne of the organization's members.
Events unfolded before him, Xehanort and his plans were revealed and so is Sora's destiny in their hands. Yet Saix paid no attention, he himself feeling rather confined to his new being.

And then he appeared.

"The name's Lea!" The read head announced, a nostalgic glint sparkled in his eyes, one that Saix had almost forgot "Got it memorized?"

And that's when Saix begin to move. It was spontaneous and involuntary, Claymore, his weapon appeared in his grasp and he swung it against Axel, the momentum pulling his hood backwards and revealing his face to the surprised 'friend'.

"Isa!" Was all Axel could say, looking surprised and betrayed at the same time.

This was it.
He had a purpose.

Darkness had swallowed him.

This was rather a sketchy headcannon I wrote for Kingdom Hearts, as I was rather pained by it after watching the scene in KH3D. I was planning for a Xemnas x Saix but then Axel snaked his way in and I'm not even sure what ship is this fic sailing on right now. Well anyway, I haven't really written anything that is not Ai No Kusabi related and it felt rather weird. I mean, I'm not even sure if this kind of angsty story is accepted...so leave me a comment and tell me what you think? I hope you enjoyed it though, thanks!