Kazuki Kenmoto, a Japanese high school sophomore, was punching a bag in the school gym. His light brown hair was drenched in sweat and his teal eyes were focused on the target in front of him. He was wearing a dark blue tank top with "One Punch" written in white and shorts of the same color. Suddenly, he felt a hand on his shoulder. He turned around to see Yuto Nakamura-Sempai, the captain of the boxing club. Yuto looked down at him with brown eyes and natural blond hair that shone wet with sweat. As usual, his gentle smile, which won the affection of most of the girls in the school, was plastered on his face.

"What's the matter, Yuto-Sempai?" asked Kazuki.

"As usual, you don't hear anything when you practice. I already tried to tell you twice, but it's time to close the gym. The others are already gone," Yuto said.

Kazuki took his gloves off and looked around. The gym was empty now except for him and Yuto.

"Sorry, Yuto-Sempai, I'll change right now," Kazuki said and went to the changing room. But soon, Yuto joined him, "Wait, I'll go with you."

The two of them arrived at the locker room and started to change into their winter school uniforms, consisting of a dark blue jacket, jeans of the same color, a red tie and a white shirt.

"Kazuki, your sister should be back next week, right?" asked Yuto.

"Yes, why?"

"I wanted to throw a party for her return from her year abroad. Do you know the exact day?"

"No, she hasn't told me yet, but I think she's coming back this weekend."

"Okay, let me know when you know the exact day."

With that, Yuto had finished changing his clothes. He went to the door and said "Bye, Kazuki. See you at the training on Monday," and then he left. A short time later, Kazuki had also put on his uniform and left the gym calmly. On his way home, he could not help but be excited by the thought that his little sister Yui would finally return soon.

Kazuki and his sister had been practically inseparable since their parents had left them ten years ago, and he would do anything to protect her. Just to be able to do that, he had decided at the beginning of high school to join the boxing club of the school. But everything changed about a year ago when his sister told him that she had received an offer to study in America for a year. This did not surprise Kazuki at all. After all, his little sister was a genius who, although she was two years younger than him, was already in her first year at the same school as him because she had been allowed to skip a year during middle school. The problem came seconds later when she announced that she wanted to go. Of course, he objected at first. He could not let his precious little sister go to a place where he would not be able to protect her, but after a long discussion, Kazuki realized that he could object as much as he wanted, but as stubborn as she was, she would go anyway. So he gave in and agreed to her leaving, but he made her promise that she wouldn't leave the dormitory after eight o'clock at night and that she would call him at least once a week. He had not seen her for almost a year now, but that agony was finally coming to an end. She would be back soon.

All these thoughts were swept away when Kazuki, not too far from home, noticed an unusual figure standing in the middle of the street, who seemed to be waiting for someone. He was wearing a black sweatshirt with the hood pulled up covering most of his face, the zipper open revealing a white t-shirt and dark gray sweatpants. From his build, he appeared to be a fairly thin guy, about his age, but for some reason his instincts told him it was better to have nothing to do with this person. He tried to walk past him as naturally as possible, hoping that he was not the person the guy was waiting for. When he saw that he had neither moved nor tried to speak to him, he let out a sigh of relief. He did not know why, but this person made him break out in a cold sweat. Kazuki increased his speed to get away as fast as possible. After a few seconds had passed, when he was already a few meters away, he turned around to check if the creepy guy was still there. The guy seemed to be gone.

"Good thing he's gone. But if I see him again, I'd better call the police. I don't want such a shady person hanging around this neighborhood when Yui comes back. It's strange, though. Normally, I would have chased him away myself, but it was as if my whole body was screaming at me that it was better not to have anything to do with this guy," Kazuki thought and looked at the place where the guy had been standing a few seconds ago.

Suddenly, he heard a voice coming from behind him, "Hey, persona, isn't it a bit rude to ignore someone who has been waiting for you for more than half an hour?"

He quickly turned around and saw that whoever had just spoken to him was the hooded guy from a few seconds ago.

"How the hell did he end up in front of me!!! My senses aren't that bad that I don't notice a person walking past me!" Kazuki thought and then replied, "Are you sure you didn't get the wrong person? I don't know anyone called Persona." Meanwhile, a nervous smile had formed on his face and some drops of cold sweat began to fall from his forehead.

"No, I was just waiting for you, Kazuki Kenmoto-kun. Persona is simply how you say 'person' in Italian," the guy replied.

The smile that Kazuki could barely hold back disappeared from his face and was replaced by a serious expression.

"So what do you want?"

"There is someone who wants to meet you, come with me."

"What if I refuse?"

"Of course, you are free to do so, but I was ordered by that bastard to bring you to him, so if you don't follow me of your own free will, I will be forced to use force."

"I saw that coming!" said Kazuki as he threw a punch at the guy's face, but his surprise attack was totally useless because he dodged it with a simple neck movement and said, "Sorry, normally I would have more fun, but that bastard is starting to get on my nerves by telling me to hurry, so let's end it here."

The moment these words reached Kazuki's ears, he felt a stabbing pain in his stomach, so strong that he immediately lost consciousness.

When he opened his eyes again, he found himself strapped to a chair in a room that was nothing short of surreal. He seemed to be in the middle of a starry sky, with no visible walls or floor. Next to him was the hooded person who had brought him there and In front of him, an imposing man stood with long white hair and a thick beard of the same color. His red eyes were watching him intently. He wore a long midnight-blue robe with golden ornaments and in his right hand, he held a black scepter with what seemed to be a universe encased in a bubble the size of a basketball surrounded by other universes encased in smaller bubbles the size of tennis balls.

Kazuki felt his heart pounding in his chest. "Where am I! And why did you bring me here?" he asked with an angry voice. The man smiled at him and said: "Welcome, Kazuki. You are outside of your universe, in my room, in the middle of non-existence. I had you brought here because you were chosen by me to entertain me."

"I will never be your jester, old man, so stop talking nonsense and really tell me where I am!"

"How rude of you, Kazuki. I only answered your questions, but I understand your doubts. After all, you come from a universe where things like magic and dimensional travel don't exist, right? I can assure you that you really are outside of your universe. But I guess my words alone are not enough to convince you, so..."

The man hit the ground with the tip of his scepter and suddenly, a portal opened in front of Kazuki. Through it, he saw a very familiar place.

"My bedroom!!!"

"That's right Kazuki. I have created a portal that connects this room with your bedroom. Is that enough to convince you?"

Kazuki was stunned. Until now, he had convinced himself that the surreal appearance of this room was due to some kind of special effect, but he could no longer deny the reality. After all, he could even smell his not-so-clean room from the portal. After a deep sigh, Kazuki replied to the man, "Yes, that's enough. I understand that you're probably not lying, but I have no idea what you mean by 'outside your universe'. Are you telling me that I am in another universe now?"

And the man replied with an irritating smile on his face, "Not exactly. The room we are in now is not part of any universe. It is a room that I created, outside of any universe or multiverse. But don't worry, soon you will have the chance to visit many other universes than your own."

Kazuki had not quite understood what the difference between this room and a real universe was, but the answer had more or less satisfied him. However, what the man had added at the end of the explanation worried him.

"What! I have no interest in visiting other universes. I just want to return home!"

"Ah, that's too bad, because from now on, your job will be to go to different universes and carry out missions given by me!"

With that, the man pointed his scepter at Kazuki. A tiny blue spark came out of it, which entered Kazuki's chest without causing any damage, and soon after that, a huge portal appeared under Kazuki and the hooded boy, which began to suck them in. Kazuki began to move roughly, trying to free himself from the rope that bound him to the chair, while he yelled at the man, "What the hell are you doing?!"

But the man completely ignored Kazuki and turned to the hooded boy instead, "Enea, you take care of explaining the rest to him. I just sent you all the necessary information."

The guy named Enea complained, "Why should I explain the rest to him? You already know that I'm not good at explaining."

But he, too, was completely ignored by the man, who just continued to stare at him. After a few seconds, when only Kazuki's head was left in the portal, Enea, whose torso was still visible, sighed and then said: "Alright, I'll do it, I don't have a choice anyway, do I?"

At this point, Kazuki's head disappeared completely into the portal and everything went dark for him.