AM I A DEMON?

INTRO

The battle at marineford was getting more and more serious as Ace, in a last attempt to save Luffy, used himself as a shield and tried to protect Luffy. He succeeded but ended him getting a magma-coated fist to his inside. His last words, 'Thank you for loving me' snapped something inside of Luffy. 

Without any warning, Luffy let out a blood-curdling scream as he transformed, glowing with a red chakra flowing through him. With one punch he sent Akainu flying far away, just as he looked at Ace, his breathing becoming shallower by the second and touched his wound, which healed in front of everyone's eyes.

'Luffy-Kun?', Jimbei looked at Luffy with a questionable gaze and of course, wide eyes

'Ace's little brother!!', Marco shouted.

Taking an unconscious Ace in his arms, Luffy teleported to him and said, 

"Take Ace and Whitebeard and leave, I will come after stalling them for a while"

"Wha-"

"Don't question it, just go. I'll be back, I promise."

"Okay! Pops, everyone, let's go"

Nobody was more surprised by the events at marineford than Garp himself. He didn't know what to think when his grandson just transformed into some sort of glowing thingy and took down an admiral with one punch. 

"Tailed beast bomb"

It was just after that when Shanks arrived. Seeing this as his chance to leave, Luffy instantly teleported to Moby, his red chakra gradually fading away as he collapsed on the deck. Marco, spotting him, instantly took him to the infirmary where the nurses along with Law checked on him. 

A few hours later, Ace woke up. The first person he spotted in the infirmary was Thatch. He was sleeping soundly while the nurses were running here and there for some serious patient.

"Wha-"

His words were cut off by a hug from none other than Marco.

"Ace, you gave us such a scare-yoi"

"Luffy- is he-is he okay?

"I don't know, honestly -yoi. They are having surgery now"

They sat in quiet silence, watching the nurses scurrying by, with bandages, cotton, medicines, and other medical equipment.

"Will he- he will be okay, right?" Ace asked in a shaky voice "I- I can't lose another brother"

Marco just hummed, reassuring him that Luffy will be fine. He chose to ignore his losing another brother part, he'll ask later when he is okay.

"That brother of yours though, he's quite tough and strong -yoi. Told Pops he's gonna be the king of the pirates."

"That has been his dream, always" Ace chuckled

Jimbei came in just then. Seeing Ace awake, he decided not to overwhelm him and silently handed him Luffy's strawhat. Turning to Marco, he said, "A revolutionary ship has been spotted. Maybe they are here for Ivankov. The others are waiting for you in the top deck, second-in-command"

"I see, I'll get going then, Ace, try and get some rest -yoi"

Ace nodded, too tired and emotionally drained to say anything, and went to sleep, hugging the strawhat in his sleep.