Disclaimer: I do not own Overlord and One Punch Man or anything that might get my ass sued. This is purely a fanfiction, and I get nothing from writing this except fun.

English is not my mother tongue and my writing sucks, so read at your own risk. Enjoy!

Chapter 4

"Hail Ainz Ooal Gown" – Normal Speech

Hail Ainz Ooal Gown – Thought

"Hail Ainz Ooal Gown" – Flashback

Ever since Saitama became too strong, there was only one foe who could ever best him: the damn mosquito. But today, he found himself a new threat… a woman in love with him.

"Wait a minute…"

Without any warning, the girl suddenly pounced on top of him. The young woman somehow managed to knock Saitama down to the ground on his back.

The hero could feel something soft on his crotch. When he opened his eyes, the girl was sitting on top of him.

"I didn't mean that-"

The bald man tried to correct himself, but the girl did not listen and proceeded to tear off his new clothes given by the captain with a crazed face and drools coming down from her mouth.

A shiver went down his spine, but the bald man was too inexperienced with women and too shocked to do anything.

"Get off him, Zesshi."

The captain came to his rescue and tried to pull the crazy girl off Saitama.

"Aah!"

But the girl proved to be too strong for Keisuke and swatted him to the side against a wall as if he was an annoying fly, then continued what she was doing.

After realizing he was going to lose his wizard status, Saitama finally reacted and pushed away the girl on top of him with both his palms.

*crash*

But too much force was put behind it, and the crazed girl was sent flying to hit the ceiling, cracking it.

When he saw what he just did to a person, Saitama disappeared in a blur to where the girl was falling to and caught the petite girl in a princess carry. Ceiling debris and dust fell on his head, but he was not bothered by it.

"My bad… Are you okay?" Saitama asked the semi-unconscious girl in his arms with an apologetic face.

After having recovered in a few seconds later, instead of calming down the mad expression returned to the girl's face.

"After all this time, I have finally found someone stronger than me. Fufufufu! Impregnate me, Saitama! Our children will be the strongest!"

"Umm…"

Saitama struggled to find what to say to that. His mistake of carelessly accepting Genos as his disciple was one thing, but this was something else. Firstly, this was the kind of decision that he would have to commit to for the rest of his life.

Secondly, Zesshi looks like a 13 years old teenage girl. But that also meant he could not be too harsh on her, especially with the guilt he felt after he had accidentally hurt her.

Lastly, her face was that of a determined person like Genos when he was begging him to be his disciple. So, his best option was…

"You're still too young. Maybe, wait until you're older. Hmm."

Saitama nodded to himself in approval. This is the famous delay tactic, a common troupe in manga when an obviously illegal young girl asks the protagonist to marry her and the protagonist tells the girl to wait until she's older hoping she would grow out of it. The bald hero never thought that those tasteless mangas he regrettably read when he was younger would become useful today.

"Older? But I have already waited over a hundred years for this!"

"What?!"

The girl's reply was unexpected, so the bald man was confused.

"Saitama… Zesshi is way older than she looks…"

His answer came from his new friend who was still struggling to get back up.

"Are you serious?!"

His plan backfired completely. Now, he is in a worse position because his original plan implied that he was willing to fulfill her wish.

"Now, we can start!"

Zesshi started to move her right hand toward his crotch area. Sensing what she was trying to do, Saitama subconsciously dropped the petite girl to the floor on her butt and stepped back a little bit.

Saitama's brain went into full hyper threading mode, more than when he had to come up with the BS for when Genos was asking him questions.

"No! Wait… That's not how it works. Ahh yes! Before a child can be conceived, many steps have to be performed first."

"Like what? From an image book in the treasury room I've read, I just have to put your—"

"Like dating! Let's go on a date first. Hmm yes, that's how it works. haha…"

He was definitely not sure what he was doing.

"Then let's do this "dating" thing."

"Right now?!"

"Zesshi, the Council have to approve of this first. Also, Saitama is supposed to go to the treasury room with me." Tadakatsu interjected.

"The Cardinals? I don't care about them now that I've found Saitama. This place can burn to the ground for all I care."

The captain frowned at her words and the air in the room suddenly became tense.

"Hmm… Why not come with me and the captain? You can show me around for our…date."

If Zesshi was asked to summarize her entire life, she could do it in one word: monotony.

Zesshi enjoyed only one thing in life, and that was fighting. When she was but a child, she chose to learn how to fight because she wanted to become strong enough to defeat her father, the Elf King, to avenge her mother.

But she had grown to love it over time. Countless fighters of the Slane Theocracy including the past Godkins that she had sparred with, and great beasts she had slain in her early days when she went on missions. The adrenaline, the blood spilt, and the joy of victory over a strong enemy, she enjoyed every moment of it.

Her world view also began to warp. She had come to to believe that only strength matters in this world. Her thirst for revenge vanished when she realized that it was her mother's fault for being too weak.

Zesshi awakened her Godkin bloodline by the age of 13 and before she knew it, she became too strong. Ever since then, her life had become black and white. No one was strong enough to fight her again.

But she was hopeful that one day she would find someone that can defeat her. That person would become her mate no matter how deformed or ugly he is. Their children would become the strongest in the world. Stronger than her father's.

Her existence had been kept secret from the world for most of her life and the last time she went on a secret mission was over a hundred years ago.

She was fine with that. The only reason she was staying with the Slane Theocracy was because they have more information, so she would have more chance of finding those stronger than her. The things left by the Six Gods in the treasury also provided her some amusements. Like the Rubik cube, or the image books that first taught her how children are conceived. She had never left the vicinity of the treasury room for a long time, but she did not really care about the outside world as strength is what really matters.

However, the men that the Council wanted to be her partner have been nothing but weaklings. One of the Cardinals also told her that the so-called Platinum Dragon Lord was weaker than her. Simply, there was no one stronger than her in the world… until today….

"Heh… so many shiny things in here. These stuffs look like they come out from a fantasy RPG game."

Until today when this man came. She finally found someone stronger than her, and "Saitama" is his name.

They were in the main hall of the treasury room. Her mate started turning his head left and right to look around the moment he stepped into the room. She was impressed too when she first came in here, but this was the room that she had been guarding for most of her life.

It was because the main hall was packed with high quality items and equipment left by the Six Great Gods for humanity. It was a large circular room with about 100m in diameter and 35m in height. The room was also gilded with gold in various places. Marble columns along the wall held the ceiling up. Magnificent chandeliers were attached along each of the column to light the room with magical lights. The ceiling was painted to display the glories of the Six Gods.

Six armor stands were spaced out in a certain interval along the wall. Each one of them was dedicated to each one of the Six Gods' combat equipment and personal items. The middle was a large section dedicated to all the other items such as weaker weapons, armor, books, sealing crystals, etcs with known and unknown properties. They were arranged neatly in shelves, on pedestals, and etcs. They were all incredibly powerful items that only a small number of privileged and skilled people will ever get their hands on.

There was another secret room that one can only enter from the main hall which stores two of the greatest artefacts left by the Six Gods, but only a few people including her knew about it and one would need their permission to enter it.

Saitama suggested coming here for their "date" which was necessary before they can mate. She did not understand why though. She never had the chance to learn much about the opposite sex because she rarely had any interaction with other people. When she was young, her focus was on getting stronger. The only times she went outside of the Grand Cathedral ground were during the few missions she got in which she did not have much interaction with her teammates anyway, and the last mission she got was over a century ago. She did not care because all she needed to know was how to make children.

"The Six Great Gods had left us many treasures, so that once they went away, humanity can still protect themselves. What's an RPG game, Saitama?" Keisuke answered Saitama's question.

"Oh, something from my world that you play when you're bored. It's like a simulation… magic? in which you can do a lot of things in like fighting monsters for fun."

"Why don't you just do that in real life?"

"They are for the normal civilians who can't fight like us. But for me, I play it because the monsters can't fight like me."

"Hahaha, I can imagine that."

They are ignoring me!

"Saitama, how does this "date" thing work? What do I have to do?"

Zesshi cut their merry conversation. That got their attention, and Saitama turned slowly to face her. Sweat could be seen on his face.

"Hmm… You really don't know what dating is?"

She did not understand what they were doing. The image books depicted to her clearly how babies are conceived. What they had been doing was none of it.

"Yeah, what is it?"

After her respond, the captain whispered something in Saitama's ear which she could not hear.

"What?! Really?"

Keisuke nodded slightly and a pity expression appeared on Saitama's face.

"So hmm, why don't you show me around, Zesshi? You are the guardian of this place, right?"

"Is that it? How does that help us birth our children?"

"Zesshi, why don't you recommend Saitama something that would suit him?" Keisuke suggested.

"Something that would suit him? Hmm…" Zesshi thought deeply. "What about the Divine Chavalier Armor?"

Zesshi pointed to a set of armor in the section dedicated to the God of Light. What she recommended was the personal armor left by the God of Light himself, Alaf Alah. It was a shiny silver full body armor. Saitama deserved one of the strongest equipment in her opinion.

"No, the divine treasures are reserved for the top members of the Black Scripture, and it has to be approved by the Council first." The captain shot her recommendation down.

"Why not? He's stronger than all of you weaklings."

Zesshi was granted access to all the treasures beside the two artefacts in the secret room. That was because she deserved it for being strong. So was her mate.

"It's okay, Zesshi. I would rather not wear some heavy armor that would restrict my movement."

"How about the Sword of Eternal Flame."

"That one is also a divine treasure, Zesshi."

"Nah… I don't need a weapon."

"Then, what do you need?"

Zesshi was deep in thought, but while she was doing that, Saitama was looking around.

"Hooo! What is this?"

What Saitama found was a set of clothes that is comprised of a blue skinsuit with a logo on the chest that has a "S" symbol, a pair of red boots, and red cape.

"Those junks? The Six Great Gods call the set a "skin". It has no enchantments whatsoever beside being indestructible when worn, and you can change its size and color. Why bother with it?"

Despite her evaluation of his choice, Saitama began to put it on. Just like any magic items, the skinsuit changed its size to fit its wearer. The skinsuit hugged tight to his body and it highlights Saitama's muscular body on full display. Even if she did not have much experience with the opposite sex, she thought he was very handsome.

"Hmm… too tight and not my color. You said I can adjust the suit, right? How do I do that?"

"Say the command word "Customize Skin", and imagine how you want it to look, Saitama-san." the captain answered.

"Okay… [Customize Skin]"

Saitama said the command words and closed his eyes to imagine. Then the original blue color of the suit began to change to yellow. The red cape and logo on the chest had also been changed to white. But disappointingly, he also increased the size of the suit to make it less tight which reverted him back to his original uninspiring form like before.

"Much better. How do I look?"

"It's like your old jumpsuit, Saitama. It looks good on you." Keisuke complimented.

"Thank you."

"I wonder what that "S" symbol means." the captain wondered.

"Hmm, that looks like the letter "S" in one of the languages in where I'm from. It's the initial of my name if it was written in that language."

"Ess?"

"Yeah, that's how it sounds like."

"How about S for Saitama?"

Zesshi smiled.

A/N: Sorry for the long wait. This is a short chapter too. I have been busy. Also as expected by myself, I am not good at writing romance and relationship building between two unorthodox couple, so I was reluctant to write as I don't want to regress in quality too much. But here you go, the next chapter. Reviews are highly appreciated.

EDIT: For anyone who hasn't figured this out yet, the picture book that Zesshi was talking about in this chapter is a Doujinshi.