Hey there, here's my first side story for my newest fic Red-Eyed Monster. I got this idea after watching an AMV that used the song one of a kind by Breaking Point.

All for the Trill

The first time it happened he had ignored the sensation that went through his body. The first time he had passed it off as a passing emotion in the heat of the battle. The first was, and would always be, the most confusing, terrifying and uncomfortable experience.

He had lashed out blindly like an innocent virgin, a virgin of war. He was fueled by nothing but fright and rage. Everything was animalistic, the crouch, the clawing, the bloodlust, the commanding growl, and the pained howl as he hovered over his fallen teammate.

He had grabbed blindly, cracking bone, shattering dreams and spilling blood everywhere. He pounced and ran on all fours. He went after the enemy like it had killed his kits. No, it had hit harder, it was as if the enemy had killed his mate AND his kits.

The first time he could stop, he inhaled the drug but stopped at the first buzz. The sight of constant fear in his prey's eyes, the shock at his power, it was exhilarating, but he had stopped, he hadn't killed.

Then it had ended, the feelings had stopped and the scent of blood hung lightly in the air, he looked into the face of a boy who had the same faith in his dream as he did his own.

The second time he hadn't had time to stop and think about it. The second time he didn't think about the tremble that ran through his body every time he landed a punch. He didn't get a chance to remember and take in the excitement that coursed through his body at the sight of all the blood.

He did feel the rage, the anger that he couldn't contain of the cowardice of the boy who once threw himself into the line of fire for him. It was like a deep boiling and surge of betrayal. He had acted without thought, only the pleasure of showing, proving something; showing that somehow, he was better.

Even if he hadn't identified the emotion then, he certainty knew it now.

The final time he had understood the perfect feeling of dominance, power and determination it brought him; it had shaken his entire being.

The hand that had struck him and the face with sick satisfaction written clearly on it had been one of the few images that stayed clear in his mind. Beyond the flaming red eyes, beyond the marking he could still see the little boy he had stuck his tongue out at.

At that moment, it hadn't mattered all that matter was the voice in his head, telling him the time, urging him on, and reminding him of the reward.

When Sakura had come back shaken from a mission and collapsed next to him and asked him what his first kill was he thought of these times. He knew that his first kill had been back at that valley when he had completely surrendered himself to the beast inside. Naruto Uzumaki was well aware that the first person her had killed, had been himself.

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1st Time fight with Haku and Zabuza

2nd time Chunin exams. He feels betrayed because Sasuke gave up just in case you were wondering

3rd time the valley of end the fight between Sasuke and Naruto. I thought it was obvious but I put it here anyway