Chapter Text
"There. I cut out all of the Lactic acid from your muscles, mugiwara-ya. You can move like you haven't overexerted your muscles for the past 2 hours now"
"I have no idea what a word of you just said means. But thanks, Torao! I feel completely freshed up!!"
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Law stared at his respirometer results of Luffy. Comprehension radiating from his crouched and tired body. Luffy, sitting cross-legged on the medic room bed, kept munching on the steak that Sanji gave him for lunch.
"You look more stressed than usual, Torao!" Said Young man said with mirth. Like there was anything funny in this situation. Standing beside him, Nami spoke up "Is something wrong with Luffy, Trafalgar-san? Should we be worried?" The woman seemed geniunely concerned. Sanji started blabbering comforting words to their female crewmate. Making the woman's eye twitch
Law sighed. "Well, since he doesn't seem to have had any problems for all of his life, I suppose not." Law shook his head. Maybe there was some mirth in this situation. Because he could feel a disbelieving smile forming on his lips. His fellow captain's nakamas threw a suspicous glance his way..
"It's just that, I think I found out why your captain eats so goddamn much" the crewmates eyes widened. Luffy's eating habits was one of the biggest mysteries on the ship. And has been so for years. Law looked at Sanji- who was looking at him like he was his saviour- with a mad scientist expression. Grinning gleefully. "He doesn't have ATP regulation in his body. All the glucose, lipids, even the proteins almost immedietly go into the cellular respiratory process. Insane..."
Sanji's face took a troubled, slightly confused expression. "Listen, I know some basics about genetics myself. But you lost me at ATP"
Law hummed. Flipping a page of the reports on his hand absentmindedly "His body never storages food. It just turns it into energy to be used. immedietly. All the time. Ive never seen something like it, but it might be why hes like a kid on caffeine all the time too"
Sanji took a momment to process what he heard, then groaned. "You mean I've been feeding a 24/7 goddamn factory everyday. Great." He muttered under his breath. His grumbling making Nami sigh.
Law's expression took a pained tinge to it "this also, mean he's a lot bunch more prone to getting cellular cancer, if he doesn't get enough antioxidants-" he turns back to Sanji "those are fruits and vitamins, Sanji-ya"
Sanji paled, looking like he was mentally calculating several diet choices in his head. Law looked back at Luffy "that means he'd probably get much, much worse than just scurvy if we were ever low on food" he said with a pointed look at the meat Luffy was eating. Probably the only sort of thing he's eaten for all of that day. Luffy guiltily shishishi'ed.
Law listened to the crewmates talking to eachother for a while, processing the information himself. He though strikes him then, "is this why you're always hungry, mugiwara-ya? Have you ever even felt what it's like to have a full stomach?"
The commotion slowly came to a stop. Everyone getting silent to hear the straw hat's response. "Hmmm, well, when I eat enough to not be able to move, everything's pretty great for a few minutes!"
Luffy bit a big chunk out of the meat in his hands.
"But that's it. then I get hungry again"
Sanji whimpered
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"How sore are you muscles, usually?" Luffy paused his stretching to turn around and see him. Law was leaning against the deck of the ship. Hat shadowing his face. The weather was quite hot. Even for summer island of new world standards.
The younger man put a hand on his chin. Humming to himself, he tapped his foot "when I was a kid, before I ate my fruit, my arms and legs were always sore. Even when I didn't do too much running around." Luffy broke out into a smile "but when I ate my devil fruit, it went away!" He nodded to himself.
Law nodded too.
Seems like he thought the rubber properties made the cause of muscle soreness disappear. Law knew better.
For once, if Luffy still could feel sore after an exercise, then the Lactic buildup didn't stop. Wait.
"Does mugiwara-ya feel sore muscles after a fight?"
"Hun."
Okay, then the normal cellular breathing rules still applied. No oxygen, no relief. So how did the straw hat compensate for the insane amount of oxygen his metabolism needed?
"Since eating that fruit, how much has your lung capacity improved?"
Luffy grinned. An impossibly wide one.
Maybe, just maybe, Luffy's fruit had saved him from a life of illness just as much as Law's had