"Ace... promise me that you'll never die!" a 7 year old boy was holding onto the 10 year old Ace.
Ace had his hair cover his eyes he looked down, with one hand on the 7 year old boy's shoulder, the other hand holding a letter.
Right now, they received the news of Sabo "Dying." and Luffy was crying his soul out.
Seven years had passed by since Ace had been transmigrated, and during this time he had forgotten a lot of information about the world.
He still remembered the key events, but the details had been forgotten.
Yet when Sabo's father had arrived to bring back Sabo, Ace remembered that the nobles were about to burn down the poor district before the visit of a celestial.
Ace had handled the situation greatly as he was very strong, in fact, he believed that he was the strongest 10 year old in history.
Sabo and Luffy were also stronger than their anime counterparts. Yet, Sabo still set out to the sea secretly, only leaving a letter for Ace and Luffy.
Although Ace knew that Sabo hadn't died, he still worried that reality was different from the manga and anime, and just the thought of Sabo's death left him teary eyed.
Ace bit his lips then punched Luffy.
"SHADDUP, REAL MEN DON'T CRY!" He shouted as a few tears fell down his face.
"B-B-UT SABO IS DEAAAAAAAAD!" Luffy shouted back.
"We don't know that for sure..." Ace said trying to convince Luffy, but subconsciously he tried to convince himself.
"YOU HAVE TO PROMISE ME ACE!!....." Suddenly Luffy shouted.
"Don't you... ever die Ace!" Luffy almost whispered.
"Smack" Ace smacked him again
"The Hell's that supposed to mean, try worrying about yourself instead, you're lots weaker than me!" He said in anger.
Even though his words were always harsh they had hints of worry behind them.
Ace had truly come to love Sabo and Luffy as his little brothers.
During the last 7 years he trained and worked hard to become strong. He didn't know how strong he was but he felt like he could easily take on rear admirals, maybe even vice admirals.
But training hard became lonely, so when he met Sabo in the woods, Ace entertained the idea of befriending him, and then Luffy appeared as well and somehow their friendship grew into brotherhood. And although Ace somewhat remembers his former life, his body and brain is still that of a child.
Most adults that knew him still found him creepily mature for his age.
"Luffy... let's become stronger and set sail for freedom when we're 17." Ace suddenly said in a moment of seriousness.
"Hn." Luffy just nodded while crying.
On the sea, a big ship was sailing from Goa kingdom. The ship belonged to the revolutionaries.
"Dragon-sama, do you think it's wise to adopt this child as you disciple? He even claims to have amnesia, what if he's a spy?" An underling asked in worry.
"Didn't you go through his things already, it's fine, if he's a spy I'll handle it." Dragon, the leader of the revolutionary army said in a dark voice.
"What should we do with his belongings? The underlying asked.
"Give it back to him, and help him to familiarise with the ship as he will stay here for a long time." Dragon commanded before leaving the underling.
".... yes sir..."
The child they had picked up was Sabo. His ship had exploded leaving him with a big scar and amnesia, but when they went through the child's belongings they found out that the child's name is Sabo.
"Tomorrow morning I'll show you around the ship, rest up until then." The underling said before taking his leave.
Sabo just looked through his jacket, hat, and things he found in his pockets. He couldn't kickstart his memories again but he found something that might help him find his memories. a Small map with destinations circled around.
"Island of sixis? find a bird with a chest in its stomach?" Sabo read in confusion.
In a Forrest outside of fusha village, Ace stood above a sitting Luffy, and held a stick in his hand.
"SMACK" Ace hit Luffy on the head.
"OUCH, HOW IS THIS TRAINING!" Luffy shouted in frustration.
"I told you that we're training your senses, try to dodge it without looking." Ace said, knowing it didn't hurt since Luffy had eaten the gomu gomu no mi a long time ago.
Ace could use Haki but chose not to since he didn't want to hurt Luffy
"Hmph, Sabo was the nice brother." Luffy grumbled
"haki infused SMACK"
"OWOWOOW HOW DOES YOUR AND GRAMPS PUNCH HURT SO MUCH!" Luffy shouted in surprise.
"SHADDUP AND FOCUS!" Ace shouted in frustration.
Teaching Luffy is like teaching a stone. It's hard.
Their lives continued like that for 7 more years, until the day finally came that Ace had awaited and Luffy had feared. It was time for Ace to set sail for the seas.
"Ace, are you sure you don't wanna be my vice-captain?" Luffy asked a final time as he stood at the shore with all the fusha villagers that had united to say their farewells.
"How about you join me as my vice-captain instead?" a 1.9 meter tall, black haired teenager said with a smile. His freckles gave him an extra charm to his smile.
His eyes were hidden by his rounded hat that had a burning skull on it.
"Never!" Luffy retorted while looking up to the muscular figure of Ace.
"But Ace, how are you going to set sail without a ship? Do you want us to provide you with one?" The mayor suddenly asked
Ace just grinned at all the people that were sending him off, as the black pearl on his ring suddenly dropped into the sea.
"Ace your ring!" Luffy said in worry. He knew that Ace seemed to care for that ring.
Suddenly the sea started shaking as a huge black ship rose from beneath it.
Everyone dropped their jaws in surprise. Luffy's eyes were flying out of their sockets.
Ace simply jumped on top of the ship and smiled at everyone. As if the ship had a will of its own, the sails fell down and the winds started pushing the ship away.
Seeing how everyone just locked aghast, Ace couldn't help but to laugh at them.
Everyone stood there as if they had frozen to ice. They saw Ace disappear into the Horizon.
Everyone awoke from their stupor as Ace waved at them, as if he was unwilling to say goodbye for the last time.
"AAAAACEEEEEE WAIT FOR MEEEE, I"LL SURPAAAAS YOUUU AND BECOME THE PIRATE KIIIIIIIIIIING!" suddenly Luffy shouted his last good bye.
-~-~-~-~-~-~-~-
The letter from Sabo is at the end of chapter 588 in the manga if you want to read it.