One Piece: Law and Disorder-Blood is Thick

Confusion

Luffy was hanging upside down on a tree limb. He had his arms crossed across his chest and he was watching the fight between Tra-guy and fruit punch man. His face was steadily getting more and more impatient as the battle dragged on that he resorted to annoying Law as he fought against Usui.

"Tra-guy..." Luffy said as the person in question did a complicated flip to dodge perilous projectiles. "If there are jellyfish, do you think there could be peanut butter fish?"

Usui smiled in amusement at the question and Law's eyes widened at the gesture, but had to throw himself to the side to avoid being impaled. Both of them couldn't use potent techniques for their own reasons. Usui couldn't kill him because of orders from a higher position, and Law... let's say he just didn't have the mental preparation to kill Sin.

Although, Usui was not afraid to hurt the older man. When Law made a mistake of remaining in the transparent cube field, he almost lost an arm to Usui's power. He quickly switched himself with an entire tree and a part of the plant's trunk was blown off. Law had managed to cut off one of Usui's arms but before he could finish the other one off, Usui flew right into his face and Trafalgar had to focus on parrying the sword's attack.

"Oh!" Luffy flipped off the tree branch and landed on his feet. "What about fire melon? Like watermelon, but fire. That would be so cool!"

"Mugiwara-ya," Law said, his eye twitching. "You are literally going to be the death of me."

"Hm?" Luffy tilted his head as Usui lunged out to slice at Law's chest. "What do you mean?"

Law mentally sighed. Both his and Usui's room flickered out of existence and their fight became more physical. The clash and clang of metal on hardened blood, heavy breaths and close calls. Frustration and impatience.

"Oi, Tra-guy," Luffy said, walking toward their battle. "If you don't hurry up, Sanji will come back and you won't be able to concentrate."

I'm already unable to concentrate, but not because of Cook-ya.

He saw Luffy do something from the corner of his eye and he grew panicked. Jumping aside at the last second, Luffy's third gear armament bulleting towards Usui. A huge crash and a cloud of dust rose from the clearing, large enough for the crew back at the Sunny Go to see.

Luffy's arm deflated and it whipped back to its original length. He chuckled in accomplishment and grinned at Trafalgar, who sweatdropped. Maybe he was wrong about thinking that this guy had any respect for other people's battles.

"You didn't need to do that."

"I was getting bored just watching."

Usui picked himself up from the crater Luffy had made and dusted off his clothes. He was bleeding, actually bleeding, from open wounds that he had gotten from both Law and Luffy.

He shook with excitement and his eyes glinted. "Fun! Really fun! What's your name?"

"Monkey D. Luffy. The man who's going to become the pirate king!" Luffy said with a straight face.

"Oh?" Usui sneered. "You've made an interesting friend, aniki."

"Aniki?" Luffy blinked.

Law gave him meaningful glance. "We aren't brothers by blood."

"Mmm," Luffy nodded in understanding. "Can I kick his butt?"

"We need him to heal Nami," Law said, "so, no."

"He's the one who made her faint..." Luffy pouted.