(Bloodline Arc)

The Kuroshi Clan is a clan that was once hailed as the strongest in the entire continent. Nobody dared cross them, be it entire countries, they could trample them underfoot. This was the clan that Kai was born in.

A clan was a place where people tied with blood gathered. Meaning that every single member was a relative of at least one other, be it close or distant. Any typical clan would hold a hundred or so at most, but the Kuroshi Clan of the past had tens of thousands of people.

They may not have gone at everything through the righteous path, but they were undoubtedly strong. Today, however, they were no more than a shadow of their former selves, if not for their numbers, they'd have long since been disregarded.

It was roughly three hundred years ago, a great war took place that claimed the lives of millions. The Kuroshi Clan was the biggest powerhouse back then, with the power of darkness that absorbed almost everything and the cunning of their members, battlefields were just trifles.

If things had gone as expected, the Kuroshi Clan would've won the war and prospered even more.

However, there was a threat that not even they could stand against. Traitors. People who were born and raised in the clan pointed their swords at their own people and poisoned their food and water. In the end, they were defeated from the inside.

If not for the timely arrival of their allies, the Kuroshi Clan would've been hunted to the last person. Unfortunately, however, only the weakest of the clan survived as the stronger ones were hunted down first.

Now, let alone being the strongest clan, they were now considered the weakest. Still, none dared to cross them due to their people that surpassed a town's number.

Kai was laying down on the wooden floor with his arm raised up.

"F-class, huh..."

He sighed. He was a far cry from being the strongest and it would take a long time before he even approached that level of power.

Just yesterday, he had learned that there were levels of power in this world starting from F through A, then S, SS, and SSS. They were also divided into several parts called 'steps', from first to fifth, though it wasn't that important. These weren't randomly given to others, they were given once someone reached a certain level represented with numbers through magic.

His goal was to be the strongest, and the strongest humans alive are S-class, nothing more.

Records spoke about the Kuroshi Clan's leader during the war three hundred years ago was at the peak of S-class, while the current clan leader was only at the peak of E-class, and though he would enter D-class soon, it wasn't that big of a feat.

Even a random kid on the street who tested for mana could be F-class, that was his level of power currently.

"Kids around seven start training. Apparently, other clans make them train from ten."

Even so, the people in the clan were still weak.

"When does our training start?"

He asked a girl beside him. She had black hair and eyes—a feature of people who wield darkness and the Kuroshi Clan. His colors were darker than most though.

"Dad said it'll be tomorrow..."

The girl grumbled.

"What's wrong?"

"It's just that... we won't be able to have as much fun as before."

Kai raised a brow at the girl's melancholic mood.

"Aren't you exaggerating too much? It's not like they're taking the entirety of our day..."

Though perhaps that was the right reaction for someone of their age. The people of this world do grow faster than most as someone at fifteen would already look like an eighteen year old on Earth.

"Then, tell me how much they're going to use!"

The girl stood up and pointed at Kai.

"Well, eight hours a day for weekdays and then we're free on the weekends. That's about it."

Considering that school took about that much, it really didn't matter to him. Besides, how could he get stronger if he didn't train?"

"That's about it?! That's practically half of our lives!"

"...It doesn't even add up to two days a week."

The girl in front of him, Kuroshi Akane, was one of the kids in his area. Kai didn't know what kind of relation they had though. He was told one time that she might've been a distant cousin. Although this was a clan where only blood relatives or those tied by marriage were allowed, it wasn't like everyone had a drop of blood in each other.

For one, if Kai married and had children, those children would only be relatives to Kai's relatives, none of which he actually knew. In that sense, clan members marrying each other wasn't that uncommon.

After all, there were more than ten thousand people here.

Akane began counting with her fingers but after a while, she groaned and asked Kai instead. Was it that mathematics in this world weren't as developed? Or could it be that the clan's education was lacking?

Many people were lacking basic arithmetic skill.

"I guess it might seem like half your life to you. You're a pretty active kid after all..."

A day didn't go by where Akane was outside playing. And it wasn't for just one or two hours, her stamina was through the roof. Even Kai was tired trying to keep up with her all the time.

"What did I tell you about calling me a kid?!"

Akane walked on top of him and stepped on his stomach.

Kai spat out all the air in his body and began rolling in pain.

"Agh..."

Being kicked in the stomach without being able to defend or prepare properly, it was pretty rough. He coughed a few times and looked at Akane with a wronged expression.

"T-that's what you get for calling me a kid, hmph!"

She pouted and turned her head to the side. It would've been cute, had she not kicked his abdomen a few moments before.

"...Huh?"

Kai sat up with one hand still holding his stomach.

"Akane, there's something in your hair..."

"Eh?"

Akane turned to him and then held up her hands to her hair. Her hair wasn't that long yet, but it soon would be. That wasn't important right now though, as Kai had just seen something weird sitting atop her head.

"There..."

Akane followed Kai's finger and touched her hair all over. After not feeling anything for a while and seeing Kai acting so strangely, she began to panic.

"W-what is it?!"

"..."

Akane couldn't see it, but he could. He fell silent as he stared at the little creature atop her head.

It was a round, purple creature. It looked like a spirit. Its eyes were without pupils, they were just glowing violet. Above its head were two small pink horns. It had a tail that looked like a curtain's ends, but it felt like it was surrounded by smoke. It had fin-like attachments to its side but it was more similar to its tail than anything.

There was also a star-shaped symbol etched into its forehead and its mouth was just a wavy line. It felt both creepy and comical to look at.

The creature saw Kai pointing at it and turned to face him. It blinked its hollow eyes cutely before opening its mouth and revealing two tiny fangs along the edges. Then, it disappeared in a puff of purple smoke.

"...Am I hallucinating?"

Kai pinched his cheek to make sure he didn't eat anything weird. Akane was still panicking and after calming her down, Kai decided to just forget about it. It was a different world, there were bound to be strange things everywhere.

Kai's Residence. Midnight.

"Are you awake?"

A childish voice called out to Kai.

"Hey, wake up!"

Because it was ignored the first time, the little creature shouted and Kai was jolted awake.

'I-it's the ghost I saw earlier... So, I wasn't hallucinating after all? Or, am I actually hallucinating right now?'

He pinched his arm and after seeing the ghost still in front of him, Kai cautiously talked to it.

"So you were real..."

"Un! I'm actually very surprised! No normal person should be able to see spirits—let alone understand them! It takes a long time along with a lot of training to temper the mind and soul."

The spirit circled around Kai, as if it was inspecting him.

“So uhh, spirit, do you have a name?”

"Yes, my name is Reo! I am a spirit of darkness."

The spirit didn't talk any further than that, maybe it was seeing if Kai was intimidated? The current mood made him feel like it wanted to ask more questions so he began to pry deeper.

"Then... what do you want with me?"

"I need your help. It isn't anything dangerous, I just want you to sign a contract with me and become my master."

"Your master?"

'What would a spirit want with a child like me? Though I’m not actually a child...'

"Your affinity with darkness is the best I've ever seen. If my instincts aren't lying to me, you're going to achieve great things when you grow up. I'm just staking my claim before other spirits can get to you."

Kai frowned for a bit before asking.

"Then, could you tell me what a spirit's master is?"

"Of course. A master, or a spirit's contractor is someone who holds a portion of the spirit's power. In exchange, the spirit can also grow along with its master. We don't actually have any physical bodies, but with a spirit's power, even the strongest would reach another level."

After receiving the explanation, Kai fell into thought. He didn't know what Reo actually wanted, if it wanted to become stronger, then couldn't it just find someone stronger than himself?

The two of them talked for a bit. He asked questions and Reo answered them patiently.

"Are you really sure about this? I don't even have any magic yet."

Kai asked one last time. He didn't want the spirit to lend him its power and then regret its decision later on. Aftter all, their contract would likely last a lifetime.

Reo clicked his tongue several times. If he had a hand, Kai would've seen him wave his index finger around a few times.

"Your training begins tomorrow, doesn't it? I told you. I believe in your potential. It's like you want me to settle for grass on the road when I could just wait for a rose to bloom. If you become my master, I'll guide you and help you become stronger."

So it doesn't matter if you're weak now. Reo said.

Kai smiled wryly. It was a lot of pressure.

"Then, please take care of me."

"Yes, master!"