For clarification, the characters refer to their biological mothers, as mother/mom, and to the other wifes of their father, as kaa-sans. That's more or less how I plan to do for all my stories, but if you have a better idea in how the kids could call them, that doesn't involve aunt, I am open for it.

Daily life of the dragon prince

"Argh!"

Issei exclaimed in pain. His entire body was aching after training with the two monsters of the crew. Monsters in the biological sense, in this case, Aggron and Tinkaton.

Aggron itself wasn't that much of an issue for the boy problem, but Tinkaton on the other hand...

...

"Is it just me, or does it look like he's slowly taking over?"

Paison asked Saul, wanting to confirm his suspicions about their youngest brother current display. The archaeologist, in turn, looked at Issei with a smile on his face.

"He took the advice well. Anyway, our family always had a talent for being wilder, so I guess tuning in to the fruit's instincts wouldn't be too difficult for him."

Saul explained with crossed arms, watching as Issei used his advantage in speed to dodge Aggron and Tinkaton's blows. Every now and then the boy manages to attack as well, throwing lightning bolts, or jets of water he generated, at the duo.

Hearing the explanation, Paison looked at Issei and then at Saul, again at Issei and then again at Saul.

"Isn't that just a fancy way of saying he's a beast?"

"Of course."

Saul answered without wasting a second thought.

A comical drop of sweat ran down the forehead of Hancock's eldest son, who decided to content himself with watching his younger brother fighting.

Aggron was having a hard time hitting Issei. The boy was moving too fast, flying around the metallic Pokemon with ease. To make matters worse for the latter, Issei constantly generated jets of water and threw them at him, while combining them with his electricity. If Aggron wasn't making use of his aura to fend off some of the attacks, the creature would likely have already been defeated.

It was Tinkaton that caused Issei the most trouble. The Pokemon's fairy aura was critical against the boy, whose only options were to run away and attempt to attack with his elemental powers. Any attack with draconic aura was ignored by the little pinkette one.

But as the fight went on, it was possible to notice more of Issei appearing than Leviathan's instincts. Like for example, when he flew up high in the sky, and scowled at Tinkaton, clearly taunting him for being too short and not being able to hit him from there. This ended with the pink one throwing his hammer at Issei, who didn't dodge it in time and was knocked down at the ground.

What followed was Tinkaton and Aggron teaming up to beat him, until the boy covered his body in lightning and managed to flee. But that was the end of the fight, as Issei's stamina ran out, and Paison had to catch him up in middle air, to stop his brother from violently falling into the ground.

...

"Shishishi, you guys had a busy day."

They currently were on the deck of the ship, Issei lying with his head in his mother's lap, who was ruffling his hair. Saul sat on the ground near his father, and Paison was in the crow's nest.

"You could have taken it easy on my little boy!"

Hancock said, with a comical "rage" at Tinkaton and Aggron.

"Tinka, tinka!"

The pink one answered with his hands on his hips. The only problem was that Hancock had no idea what he had said.

"Hey! I'm not just a mama's boy!"

However, unlike Hancock, not only Issei, but Luffy and Saul also understood what Tinkaton meant. All of the Pirate King's children had inherited one of his gifts, the ability to hear The Voice of All Things.

And of course, Luffy and Saul burst out laughing.

"But you are a mama's boy!"

And Hancock caught her son in a tight hug, rubbing his cheeks against her, and accidentally suffocating the boy, who was trying in vain to get away.

...

No longer having to train for the day, and wearing a seastone bracelet just to be safe, Issei now found himself in the ship's aquarium, along with some of his brothers and sisters, as well as other of their friends, like Zoro's children, Sanji or Usopp.

And for the moment, the boy watched, not innocently, as his sisters destroyed their friends in the deck. Rorona Ryuma looked at his defeated hand, and Edward, Usopp's son, had already given up playing and was in the corner crying.

"Didn't give up yet little boys?"

An arrogant voice came out of Mikan, the eldest daughter of Luffy and Nami. Even Issei had to admit that his sister's smug expression made him shiver.

"Hahaha. Little sister, you know that those guys don't have great learning skills, right?"

Monkey D. Mary, was the daughter of Mikita and Luffy. The blonde had the same haughty expression as her sister. The two were cross-legged, smirking at Ryuma and Edward as they brought their hands close to their chins. They, at the moment, were the perfect description of arrogant rich girls.

"They can be worse than mom and Mikita-kaasan sometimes."

Nashi, one of Nami and Luffy's triplets, Mikan's younger brothers, commented to Issei who nodded in agreement. He looked to be fifteen years old.

"Sometimes they scare me."

A female voice said, almost hiding behind Issei. She was a blonde girl with short hair, who was wearing a white shirt with a lilac skirt. Her name was Charlotte Cynthia, she was the third daughter of Sanji and Pudding.

"You're not alone in this."

Issei said jokingly, placing his hand on Cynthia's shoulder. The girl smiled back at him with slightly rosy cheeks.

"Oooohhhhhhh!"

The two could hear Mikan and Mary, and they were sure the pair of sisters were looking at them.

That made Issei look at his sisters, than look at Cynthia and look at his sisters again, giving them a thumbs up. A gesture that the two returned.

Cynthia had an idea of what type of mental dialogue the three were having, and it made her even redder. But it was no secret that she had a crush on the user of Leviathan's fruit.

They were the only ones of the same age group, Cynthia being only a year older. The crew had a few younger kids, but at least three years younger. Inevitably, inside the ship, they were best friends. The fact that Issei's sisters constantly encouraged the blonde helped a lot too.

And as for his desire to have a harem, well that was something she hadn't given much thought to yet.

"Hey, Mary, didn't we have something to do?"

Mikan suddenly speaks.

"Yeah, we did. We even need help, so you all come with us."

The blonde says, agreeing with the redhead, as she drags the rest of her siblings and their friends out, with the exception of Issei and Cynthia. Anyone who complained was dragged out by the ear.

Cynthia had blushed even more since their subtlety was on the negative numbers, but Issei was just smiling.

"Are you okay now?"

After a few moments of silence, she suddenly asked about his condition.

At first Issei looked confused, his head inclined slightly to the side as he tried to understand the blonde's question, who kept to herself that his expression was cute.

"Oh yeah, the fruit? No need to worry, everything is under control!"

He replied proudly, patting his chest, which caused Cynthia's eyes to drift back to the seastone bracelet on his arm.

"Are you sure?"

She asked again, understandably worried, as the image of a partially transformed Issei eating raw meat like a beast on the table was still printed in her mind.

But to her concerns his answer was simple.

"Absolutely!" He replied with a big confident smile, which simply left no room for doubt. "I'm not only going to one hundred percent master this fruit, I am gonna go far and beyond with it, to be as strong as possible! So, I'll make sure you don't have to worry about anything!"

He declared, almost passionately. Cynthia's cheeks grew even redder, but a small smile formed on her face.

"That's good... I also want... I want to stay strong to help Ise with everything too!"

She spoke, looking into the brunette's eyes. Cynthia never wanted to see Issei in a state like the one he was in right after eating the fruit, again.

"Chichichi, that's our promise then!"

Cynthia gently took Issei's hand, who also held her hand in return.

"Yes, that's our promise."

They still didn't know how important that promise was.

...

"Were you hitting on my daughter again, you fucking brat?"

A trio consisting of a blond man with spiraling eyebrows, a five year old boy with tied dark hair, and a tall talking skeleton, could be seen walking through the streets, carrying bags of food.

"Absolutely."

Issei replied without any hesitation. A gigantic vein formed on Sanji's forehead.

"Hoho, Issei-kun is very bold, just like how we teach."

Brook said, he was perhaps the most amused by the situation.

Sanji clenched his teeth. He was torn by the situation.

"Part of me is proud, part of me wants to kick him in the face."

The curly-browed one admitted in frustration. Issei just turned to Sanji with a smug smile on his face.

"If you did it, even if my mother didn't kill you, the kaasans would."

"Hohoho, he's right again."

Brook added.

"Tsk, yeah I know... Hmmmm, kid, you're going to learn to cook."

Sanji suddenly spoke, causing Issei and Brook to look at him in surprise and curiosity.

"Why?"

Issei asked, not looking particularly thrilled about the idea.

"Tsk. Listen here brat, if my little girl is... in l-l-lo... i-int-interested in you." It was remarkable how much of an internal struggle it was for Sanji to admit that fact. "The least you have to be able to do is cook for her as well as I can." There was a pause, and the cook stared at the child, who felt a chill run down his spine. "Not an option."

Issei ended up simply nodding his head several times, not wanting to anger Sanji. Now, in addition to his constant training with his akuma no mi, trying to master haki and martial arts, he had cooking lessons under his belt as well.

"Hey, aren't those…"

Whispers followed wherever the group passed. It was normal, after all they weren't in any random world, but in the original world of the crew. From those people's perspective they saw the feared members of the Pirate King's crew, as well as one of his children.

Issei turned his face and faced two women who were whispering about them. The two stopped, and just looked at the child in fear of what he could do, regardless of his age.

"Pretty."

He said it simply, and then just turned his face away and continued walking normally with a smile.

The women stood there stunned, notably confused.

"Heh, good boy. Hey, do you want to buy a magazine before we get back?"

It was obvious what kind of magazine Sanji was referring to. Issei's eyes shone like stars at the question of his uncle, and future father-in-law.

"For sure."

"Oh, then, Ise-kun, let me be so kind as to choose the magazines this time. But for now, would you like to know a little more about the beauty of the female body? Or the clothes? Especially the panties, yohohoho. Well, although if you're like your father, I think you'll be more like the type of man who prefers women with more pronounced breasts."

The boy nodded strongly, confirming Brook's words. His excitement was remarkable, almost surpassing that of when he was training. Animatedly, the trio chatted as they headed to buy a magazine, which the two adults judged to be "educational". Later that same day, Vivi would find said magazine, burn it, and punish Brook and Sanji. And Issei would be responsible for washing the deck for the rest of the week. Still, they would do it all over again if they could.

...

Another day had passed. After training with Saul, Paison, Tinkaton and Aggron again, and with Luffy on haki and hand-to-hand fighting, Issei had been thrown to take a shower and now, he and Cynthia were in a room with Robin, Nami and Olvia, Robin's second daughter after Saul.

Nami and Robin thought it was important for the kids to have some level of basic education. (In reality, they thought it was important for Cynthia, who watched the lessons attentively and seemed to enjoy it. For Issei it was simply a punishment, for things like accepting porn magazines from Brook or Sanji.)

The redhead took care of matters like math, especially the financial part. It didn't matter that they were practically infinitely rich, she made a point of imprinting these ideas on the children's heads.

And Robin took care of subjects like grammar and history. It was remarkable that she did this more for her own amusement than for any other reason.

Olvia was only there to supervise, and because it was a good opportunity to tease Issei and Cynthia, which was probably at the top of the list of favorite things for the boy's sisters.

"Ahhh... this is a lot, I need a break..."

The brunette said, surrendering and throwing himself to the ground. Steam seemed to rise from his head, his mind had been pushed to its limits.

"Come on Ise-kun, it's not that difficult."

Nami tried to cheer him up, lifting him up, but the boy was still limp and with a stupid expression on his face.

"Hehe, Issei is showing an uncool side to Cythia-chan."

Olvia chuckled, poking Issei's cheek, who still looked like he was having trouble while slowly processing information.

"Is not true! Ise is so c-cute now!"

The blonde, however, made it clear that she did not agree with Olvia. Which, honestly, only made Issei's older sister even happier. Not only her, but Nami and Robin too.

"But don't you find any of this history interesting, Ise-kun? Roger, your great-grandfather Garp, the monster that was Xebec..." Saying that man's name, even Robin had to stop for a moment. "It's a great story, don't you think?"

Issei finally seemed to have regained some level of rational ability, and was able to respond Robin.

"It is kinda cool, but other than Grandpa Garp, it's not like I'm going to meet any of these guys anyway."

Robin just smiled.

"It may be, but it's still something you should put some effort into trying to learn."

Issei looked like he wanted to disagree, until he felt Cynthia grab his right arm.

"Come on, Ise. Don't want to study with me?"

She asked, with a cute expression that feigned sadness. She truly knew what to do to motivate him, and as predicted, it had a critical effect for the brunette.

"YOSHI, LET'S GO!"'

'He's basically Sanji's apprentice.'

The three oldest women thought at the same time.

...

Tinkaton and Aggron weren't the only Pokemon that had joined the crew. For example, there was also a Lucario that evolved from a Riolu after joining them.

Said Lucario at the moment, was with Issei and Cynthia. Beside the Pokémon was a sixteen-year-old boy with blue hair, Kaimon, the oldest son of Luffy and Vivi.

The blue haired one had a smirk on his face, while Lucario carried a serious expression.

"Kaimon-nii! It's time?"

Issei questioned his older brother, barely able to contain his excitement.

With his younger brother's question, the smile on Kaimon's face intensified.

"That's right Ise. In addition to haki, it's finally time for you to learn how to use aura!"

and with this, I managed to write a slice of life chapter I wanted to do at least once for this fic. The rest of the chapters will still have scenes like these, but they will majorly be about events that progress to where I want to get. Meaning, unfortunately, not so many family interactions anymore.

Thoughts on Cynthia? I will be honest, she was kinda made up on a fly, I really wanted to have a character that would be either Sanji or Zoro's daughter, and that fell in love with Issei. But I already have a solid idea to where her character is going. She will also not be the only oc paired with Issei, there will be a second one as well.

It ended up as a bit of a coincidence that I did ocs in a crossover fic, but going on the opposite route of what is usally done with ocs in this fandom. Personally, never was a fan of ocs myself(I know, ironic considering a chunk of the chapter is focused on an oc), and much less in ocs that substitute the main character. So, I hope to tackle the ocs in a satisfying way.

thoughts on Issei's laugh? I couldn't resist myself

next chapter, Ddraig finally shows up

Review:

ChaosMegaEevee: Thanks for the correction