Edo Japan Arata Hiroyuki is referred to as Hiroyuki. Reincarnated Arata Hiroyuki is referred to as Arata.
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The Chronicles of Arata Hiroyuki. Date of issue: May 13th, 1921.
Diary Log 1, Day 1, Year 185X
'Arriving in this town wasn't precisely what I wanted. Still, I had arrived disoriented and unaware of my surroundings. I rented a place that was just to my liking. Today would mark the start of training my new student.'
...
From the start to the last page, this diary interested him. Despite the interest, it was horrifying and it made him paranoid. "Arata Hiroyuki," the title was simple yet it incited a strange feeling. It was easy to guess that it detailed Hiroyuki's life, and as he read it, it was confirmed.
It also included his own life as well, the one he led on Earth. It started from his birth to the moment he died and even after. Memories he had forgotten, the ones from his early childhood. This was what made him immensely paranoid and weirded out by the diary.
His life was laid out and anyone would find this creepy and strange. Especially to Arata, he was just reincarnated into a version of himself. The average person would feel the same as it included forgotten memories as well. This didn't sit right with Arata as it was truly alarming.
For what reason would anyone do this? How would they have the means to be able to do this? Many more questions continued to run in his head, yet there were no answers. For now, he'll ignore it as no possible explanation was clear. And the more pressing issue, he is in the Edo period of Japan.
In the end, he thought about his counterpart who lived here. It was strange, the diary had multiple, 'Written by Arata Hiroyuki for Arata Hiroyuki,' along the logs. This pointed toward a memory but Arata couldn't be sure, and then an outward thought appeared.
'What if… they were informed I was going to take over?' It seemed an impossibility but it might've been possible. Yet, whether it was, all this did was confuse him even more and added more to the list of unanswerable questions. Ignoring that matter, he thought about the logs themselves.
Some logs detailing the current status of that day it was recorded. Others the current state of Japan as this was disheartening to Hiroyuki. Hiroyuki was a samurai, which made Arata impressed and strangely proud. He was fascinated with samurai because his father told his younger self stories.
Disregarding that matter, he kept thinking about the diary and its logs. Halfway through reading Hiroyuki's diary logs, he stumbled across an important one. The record started normally, and it wasn't until the end that it included a historical figure.
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Arata Hiroyuki Diary, Hiroyuki Log 1XXX, Year 185X.
'...I never expected Katsujiro Okita to ask me for a favor. Especially not related to his family and his daughter. The man wants me to teach her the ways of the sword. I didn't refuse since it gave me something over the man, and it would be nice to pass my skills on to someone...'
Arata Hiroyuki Diary, Hiroyuki Log 1XXX, Year 185X
'...Okita Souji... A prodigy, the moment she came at me with a sword, I could tell. I knew she would become one of the best holders of the blade. Her talent beats mine, and I was a renowned swordsman. She only needs the time and experience to refine her skills...'
...
Arata was surprised to see Okita Souji in the diary. Hiroyuki was a fantastic swordsman. From what he had read, he knew that at least. It seemed that before taking over this body, Hiroyuki was training Okita Souji.
He still wonders about the injury he had when he woke up. It was a mystery to him, perhaps related to Hiroyuki not coming unscathed from a battle. The last log detailed him engaging somebody in a duel of honor.
Hiroyuki had won the duel, and that was the last thing recorded. After that, it went into Arata's history on Earth. It started from his birth to the end of his life. When he got to that part, chills went down his spine.
It would undeniably leave a mark on him as the diary laid out his life. Sending that to the back burner, he knew how close of a relationship Hiroyuki had with the Okitas. He knew the father of Okita Souji, and Hiroyuki was close enough for Katsujiro to ask a favor.
And seeing how Hiroyuki portrayed him, he could tell the man was closed off. But Hiroyuki was close enough for Katsujiro to ask him to teach his daughter the ways of the sword. Okita Souji, said daughter, was revealed to be a prodigy in the blade. A realization struck him.
He had yet to check out this house he was in. Setting the diary back on the bedside table, he exited the room. He thought he would first find the blacksmith room that Hiroyuki described in his house.
Hiroyuki was a blacksmith in his free time. When walking, the injury caused him pain, but he pushed on. He stumbled upon a room that resembled that of a blacksmith's. The room walls held katanas and tools for blacksmithing.
At the end of the room was a katana on the wall, centered on the wall. He felt a connection instantly when he looked at the katana. The blade looked pristine like it hadn't fought in any battles, but he knew. He knew it had fought in many and had taken many lives.
He didn't realize he had it in his hand until he swung it unconsciously. A connection like no other. Nothing else could compare to this feeling. He looked for a scabbard to sheath the katana.
There was a sheath below where the katana had been hanging previously. The scabbard matched the katana's look. It was pristine, looking like the sword. Arata sheathed it and holstered it on the left side of his garb.
He inspected the rest of the room, which looked like it was used recently. The logs mentioned tending to his katana and other people's swords occasionally. Arata imagined that this was what the records referenced.
He had a rough idea of why he was here. Hiroyuki was on his way to visit someone, and somebody decided to challenge him. The person lost but survived, and Hiroyuki was left with an injury that continued to persist.
But he felt it was healing, even though it persisted. Exiting the blacksmith room, he explored the rest of the rooms. The other rooms were just guest rooms. It wasn't an incredibly colossal house, but large enough to accommodate other people.
Checking the kitchen, he saw everything was normal, the pantry half stocked. This made him wonder how rich Hiroyuki was to get all of this. Turning around as he kept the thought in mind, something immediately caught his eye.
On a table, there was a bright blue color stemming from an object. The object's glow dimmed down, and he could see it was something he was so familiar with. It was the crescent moon necklace that his wife had given him on their first anniversary.
So many things ran rampant in his mind, but he disregarded it all. He grabbed it, and his eyes shook as he thought it was a play on his mind. It was not. It was the genuine necklace, the one from Earth. The one his dear wife had given him all those years ago.
He had put it, and he felt a shower of a cool blue light wash over him. The feeling only lasted for a few moments before it left. After a bit, he regained his cool and started thinking of possibilities of why this was here.
Was it brought over during his reincarnation?
He didn't have it on him at the time of his death, and no chance for it to be brought. The possible entity who reincarnated him? No, he didn't know if there was an entity in the first place. And what would be the reasons for bringing with him? None at all. It was an item he held dearly, but was it that important to be carried over?
'Another thing to be added to the unsolvable list... Things continue to get more weirder. Although, it is nice to see this again, even if it was stolen from Earth...'
He sighed as he reminisced about the life he had back on Earth.
'It's no use to think about that life now. I won't get that life ever again.'
Putting those thoughts away, he explored the remainder of the house. He found a calendar telling the current date, July 18th, 1862. He was correct. It was Edo, Japan, where he was and had been reincarnated to.
However, he questioned why this period. He sighed, realizing another thing had been added to his unsolvable list. He saw some writing on July 19th on the calendar.
The writing being, 'Souji's birthday. PS, don't miss this one.' Firstly, he thought that was the case, although he was surprised. Hiroyuki was here to meet somebody, and it was concerning someone close to him.
Secondly, the prominent people in his life were the Okitas and some others. He ruled out everyone except the Okitas because their relationship was the tightest Hiroyuki had. When Arata found the date, he immediately knew he was right and right about it being related to the Okitas.
Today is the day before Okita Souji's birthday. Tomorrow being her birthday, he would have to go due to the message. He thought of many reasons why he had to go, but it was most likely due to Hiroyuki not going to one of her previous ones.
'How woe is me,' he thought sarcastically. It wasn't an issue to go. He read how the Okitas were. But reading is not the same as meeting the person you've read. This would also satisfy his samurai side of passion for his past life. He would meet one of the greatest samurai and swordsmen, even if it were another version of the person.
He held the crescent moon necklace next to his heart as he thought about his new life. When transported here, he was in the space of the root and viewed it. Not being absorbed, a force pulled him away from the space. He woke up in a new environment and with an injury that continued to persist. A diary of mysterious circumstances detailing the life of Hiroyuki and then his.
He exited this house to find out he was in Japan, in the Edo period of their history. Finding a blacksmith room with a sword, he felt a connection to it. He learned more about Hiroyuki and his link to one of the greatest samurai, Okita Souji. He is the teacher of said person and has the skills to mentor her.
As he kept thinking, he viewed the window and found it was night. He looked at the night sky and then went to bed, not before checking if Hiroyuki had a present for Souji prepared in the house.
Arata found the gift in the blacksmith room: a sword with a scabbard and a note. He set them on the table, where he discovered his necklace earlier, and went to bed. As he went to bed, his necklace shone like the moonlight. Arata didn't notice and had gone to bed.