This is extremely short, but it's how I imagine the scene going if Luffy was more skilled and not quite as stupid.
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"So," Luffy began, unwaveringly glaring at the large fish-man who was sitting on a throne, wearing a smug grin. "You're the bastard that made our friend cry?"
Arlong let out a typically antagonist-esque cackle. "You sure talk big for a puny human. You two, get him."
Two of the many fish-men littered around Arlong Park walked forward, wholly confident that they could defeat any human. Fish-men were superior, weren't they? Not even Gold Roger could hold a candle to them! But their inner ramblings about superiority were cut short as quickly as their heads collided, courtesy of the pint-sized human who overpowered them. Arlong was the first to recover from the shock – it wasn't impossible for the strongest humans to compare to the weakest fish-men. He stepped in front of the intruder.
Luffy looked on, unimpressed as Arlong began to monologue about how inferior humans were. "-so you see, you humans can never hold a candle to me."
SWISH.
The crowd, including Nami gasped and watched in confused horror as their tormentor choked to death on his own blood. All the while, Luffy stared into the panicked, fearful eyes of the self proclaimed superior being, relishing the sensation that only accompanied justice – not to be mistaken for the Navy and their twisted absolute justice – being served.
"Wait a second! What just happened?" asked Nojiko. She wanted to cheer, but couldn't make heads nor tails of what she saw.
"Look at what Luffy is holding," Zoro simply replied.
"Bu- his knife? I thought it was just for show, since he never used it!" Usopp exclaimed and sure enough, the knife usually sheathed across Luffy's lower back was now in his hand with the edge of the blade covered in blood, having just sliced Arlong's throat.
"So quick," Nojiko whispered in disbelief.
"Nami," Luffy suddenly growled, causing everyone present to look at him in apprehension. "You're mine, got it?!"
Nami's gobsmacked expression and beet red face left little doubt that she misunderstood what their captain meant by that, but no one was going to correct her. What fun would that be?
Zoro, Sanji and Usopp stepped forward. "Now," Luffy said as he raised his knife horizontally in front of his face and grinned manically. "Who else wants some?"
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Thanks for reading!
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