Disclaimer: One Punch Man and Harry Potter are not mine to own.

'I am in another world, somehow wizards exist, they are humanlike,but... I WILL NOT BE BACK TO PREPARE SENSEI'S DINNER!' Genos internally panicked. He hopes his Sensei will be alright.

'I failed my duty as a disciple! But now, I am in another world, I need to find out how to get back!' Genos thought.

"Old man," Genos called out to Dumbledore.

"Call me Dumbledore. How may I help you?"

"You said you're a wizard right? Can you send me back to my world?"

"Your world?"

"It's...complicated,"

"Perhaps I could help you if you could tell me more about you and why you came here."

Genos, not wanting to disclose any sensitive information yet wanting solutions said,

"Call me Demon Cyborg. I had an encounter with a certain monster and woke up here."

Dumbledore, now processing the informantion thought,

'Demon Cyborg... sounds like a name a villain would have. An encounter with a monster? Well, that raises more questions than it answers.'

The other headmasters had already left a while ago since Dumbledore started talking.

Dumbledore, only now noticing Harry's presence said to him,

"Harry, you may return to your dorm first. I will be having a little chat with this Demon Cyborg for a while."

"But...where did he came from? How can he fly without a wand? How can he shoot fire from his palms? How-"

"Harry, even I don't know the answers to your questions. That's why I will try to get the answers from Demon Cyborg himself. Now please, head back to your dorm."

Not knowing how to reply, Harry just said,

"Alright..."

And he left the pitch, leaving only Dumbledore, Bagman and Genos at the pitch.

"Bagman I would like to talk to this man in private. You may take your leave."

"Certainly, Dumbledore."

After Bagman left , Dumbledore turned to Genos.

"How about we talk in somewhere more comfortable?"

Not having any other options, Genos nodded.

At the Gryffindor Common Room

"Woaaahhh! Did you see that blonde teen! He was so badass!" exclaimed Ron.

"But we still don't know who he is. He might be dangerous." Hermione said back.

"Yeah, but he was still so cool! Did you see how he shoot fire from his palms!" said Dean Thomas.

"Yes, but how can he do it? He clearly wasn't using a wand!" Hermione couldn't believe it. She planned to go to the library later to do some research about wandless

"Well, who cares? You can't deny he was cool as hell!" Ron said.

"What do you think Neville?" Seamus Finnigan asked.

"Well, he was sort of cool..." Neville answered with his usual timid tone.

While everyone was discussing about the blonde they just saw while Harry was deep in thought,

"Who was that Demon Cyborg... Even Dumbledore doesn't know about him... Is he good or bad... How does he fly without a wand... Guess I have to wait for Dumbledore to get answers.'

"Harry!" Ron called out. Waking Harry from his train of thought.

"Huh? Um...wh-wh-what?"

"How does it feel to stand next to that blonde teen?"

"Well, he was sorta cool... but he was kinda menacing at the same time. Dumbledore also called him Demon Cyborg, so that might be his name,"

"Really? Wow!"

As the Gryffindor's continued discusssing about the Demon Cyborg's badass moves, Ron asked a truckload of questions to Harry.

As Genos followed Dumbledore to his office, he scanned the place to get familiar with his surroundings. Many places like the halls were filled an unknown source of energy (magic, Genos assumed). But a certain broom closet on the second floor was radiating a different type of energy which Genos presumed that it was another type of magic.

As they reached an entrance with a phoenix statue, Dumbledore said,

"Sherbet Lemon,"

The phoenix statue then turned around revealing a small narrow staircase.

"Come on now, Demon Cyborg."

Clearly not trusting this place, Genos charged up his incineration cannons just in case anything happens.

Genos saw some sort of fire bird as soon as he entered the room. Thinking that it was a kind of monster, he aimed his incinerations at it, prepparing to kill it.

Before the Demon Cyborg could do anything, Dumbledore immediately stopped him,

"Demon Cyborg, that is just my phoenix, Fawkes. He means you no harm and there is no need to attack him. I would also prefer not to have my office in ashes."

Genos believed him for now, and cooled down his cannons but he still kept his guard up in case anything happens.

As Dumbledore sat at his desk and told Genos to take a seat before saking him some questions.

"So, Demon Cyborg. You do not know how you came here?"

Genos nodded.

"May I know how can you possess such power without the aid of magic?"

"It was due to my cybernetics, making me a relatively strong cyborg."

"I have never heard of the term 'cyborg'. May I know what that means?"

"It's something like a half robot-half human."

"Okay... May I know more about your backstory?"

Although reluctant, Genos thought that it was best to gain trust of others in this other world.

Little did Dumbledore know, he was going to hear the longest backstory in his 150 years of life.

"Four years ago... I was a normal human and was about 15. I lived a peaceful and relatively happy life together with my family at my world. But one day, a crazy cyborg went out of control and attacked our town. A runaway cyborg... I supposed a failure in his body modifications generated an irregeluarity in his brain. He destroyed everything. Parks, schools, buildings, my house... He even took the lives of my family. Miraculously, I survived. I was just a weak, 15 year old boy, alone in the ruins of my town and at the end of my strength. Just then, a professor by the name of Kuseno happened by. He was a professor of justice on a journey to stop the violence commited by the rampaging cyborg who attacked my town. I asked him to perform a procedure to modify my body. Then I was reborn as a cyborg for justice and promised Professor Kuseno that I would someday destroy that rampaging cyborg."

Although Dumbledore was a patient man, this was starting to get on his nerves.

"Four years have passed, I was 19 and was rambling from town to town exterminating evil. I had defeated countless monsters and evil organizations. But I had turned up no clue to the rampaging cyborg, I was spending my days in irritation and impatience. And then, not long ago, a mosquito monster showed up and I let down my guard. I never imagined anything but that rampaging cyborg to defeat me, so without analysing any data about my opponent, I rushed into the fight. It resulted in the monster with immense strength defeating me. When I thought that I was about to die, my master, Saitama defeated that monster with ease. When he saved my life after Professor Kuseno saving me once, it increased my already heavy sense of responsibility. After that, no matter what, I cannot die until I destroyed that rampaging cyborg. To that end, as a cyborg of justice, I must continuw to fight evil until I encounter that cyborg once again. I must get stronger. When I saw Saitama Sensei punch when he defeated the monster, I realized that I must study under him.If only I could be that strong... I have an arch enemy that I must defeat! From that day onwards, I started following on destroying more montsers. He wanted to be a hero, so I followed him and took the Hero Associaton test. I ended up in Class S whereas he ended up in Class C. One day, a meteor appeared, threatening the lives of those who lived in City Z and the neighbouring cities. Me and another Class S hero, Silverfang went to stop it but we failed. Even with new upgrades, I failed to destroy that meteor. It was until then, Saitama Sensei came and destroy that meteor. He saved my life once again. I owe him so much. And then, a monster who goes by the name of Deep Sea King came, defeating multiple heroes. He defeated me and I was saved by Saitama Sensei once again. But he didn't want to claim any of the credit, he just said that he was a fraud and gave the credit to the other heroes. He was so heroic. A few days later, we were called to the HA headquaters to hold a meeting. The building suffered a tremor. When me and the other heroes came out, we found that the city was completely destroyed. When the whole incident ended. Saitama Sensei defeated their boss, claiming that the latter was the strongest he had ever faced..."

This continued for another half an hour or so until Genos finished explaining. By then, Dumbledore was sweating at how much this teen has gone through and how detailed he explained it.

Deciding to ask just one more question, Dumbledore said,

"Okay...Just one more question, what do you mean 'my world'? Did you come from another planet or...?"

"Yes, that is what I pressumed. I believe that I may have come from another planet or universe."

That gave Dumbledore more questions to ask.

"So you are unsure on how you got here and how to get back, am I right?"

"Yes."

"I didn't know beings from other planets look to similar to us."

"To be honest, I was quite suprised as well."

"If that's it, I will try my best to get you somewhere to stay for the time being."

"Hold on." Genos said.

"Hmm?" Dumbledore replied.

"I also have some questions to ask you."

"Oh?" That caught Dumbledore off guard a little.

"First question, if there are wizards in this world, are there non-magical humans as well?" Genos asked away.

Sipping some lemon sorbet tea, Dumbledore answered,

"Yes, there are. We wizards refer to them as muggles. We wizards hide our existence from them and although you are not a wizard, you possesss abilities unobtainable by the average muggle, so please refrain from using them at their pressence."

"Okay." Genos said, taking note of the information.

"Second question, what is this gigantic castle for?"

"This castle is called Hogwarts. It is a school for wizarding children and I am the headmaster."

"Third question, how much of this world's population are wizards?"

"Not much, around only one tenth of this world are wizards. Maybe lesser."

"Fourth question, are there monsters in this world?"

"Well there are many different creatures apart from animals but they aren't exactly monsters. Most of them are harmless like house elves and goblins but there are some dangerous ones like the basillic. Here is a book about them if you would like to know about them more."

Dumbledore handed Genos a booked titled 'Fantastic Beast And Where to Find Them'. Using his amazing speed, Genos finished the book within a minute and took note about everything. Dumbledore looked in suprise.

Satisfied with the information he had gotten, Genos said,

"That's all I have to ask for now. May I know where I might be staying at for the moment?"

"I will let you stay at the Gryffindor dorm for the time being before finding somewhere better. Letting you stay in Hogsmeade might be a bad idea. You might encounter a lot of journalists there."

"Alright then, I will take my leave."

"Let me bring you there, you may need some help if you encountered a ghost or if you get lost, especially with the stairs."

"Alright. What do you mean by 'the stairs'?

"You will know sooner or later."

After walking for a while, and encountering a few ghosts who are fascinated with Genos cybernetic body, and maybe walking on some very weird stairs. (Genos was puzzled on how students won't get lost here). They finally reached the entrance to the Gryffindor common room. They saw a potrait of a fat lady who moved and asked,

"Password?"

"Caput Draconis" Dumbledore said and the Fat Lady's potrait swung open, revealing the common room that was covered in red.

Some students were still talking about the Demon Cyborg whereas some were reading books while Hermione is doing some work about S.P.E.W. Harry and Ron were talking about what will happen to the former's first task and what could be the second task.

As soon as the students saw Dumbledore, they immediately greeted him,

"Good evening, Professor Dumbledore!"

"Good evening. Students, I introduce you to Demon Cyborg. He will be staying with you all for the time being until we find somewhere more suitable he can stay at." Dumbledore said while bringing Genos into the room.

"WHAT!!"

"WOAAHHHHH!"

The students reaction were expected by Dumbledore. What do you think of the odds that a wizardless teen who can fly and shoot fire stay with you for a night?

"Ok everyone. Mr Demon Cyborg is still our guest and he is not here to be interviewed."

""""Yes Professor Dumbledore!""" the students replied enthusiastically.

"Alright then, Demon Cyborg. I will leave you here for the time being."

Genos just noded.

Before he left, Dumbledore reminded the students,

"Remember, Demon Cyborg is our guest. So give him some privacy and don't ask him too many questions,"

Too bad none of them listened.

Just as Dumbledore left the room, a ton of students rushed to our favourite cyborg, asking questions so much that even Genos enchanced hearing cannot pick up what they all said.

"HOW DID YOU FLY LIKE THAT?"

"DOES YOUR ARM FEEL HOT AFTER SHOOTING FIRE?"

"HOW ARE YOU SO FAST?"

"WHERE ARE YOU FROM?"

"WHY ARE YOUR EYES BLACK AND YELLOW?"

Genos decided to answer some of their anwers first before observing the place.

"First, I can fly like that because I am a cyborg. Second, I am not from here and that is all you need to know. Third, my arms are made of metal and have no nervous systems so I do not feel heat from my flames. That is all I am going to answer, so no more questions." Genos said sternly.

The students then quieted down (after 10 minutes) and resumed on what they were doing.

Genos doesn't really like the red colour walls of the place as it reminded him of violence but he guess he had to go with it. The place was overall simple and had nothing special so Genos just went to sit the sofa in front of the fireplace, wondering about how his Sensei was doing.

That's it for this chapter! I originally wanted Genos to stay in the Hufflepuff dorm but I don't know how it is looks like. In my opinion, it is a little OOC but I will try my best to make their personalities fit their characters. Once again, I appreciate any constructive criticism and reviews on how I can improve my story. See you all in the next chapter!

Homework amount is killing me right now but I will try my best to update as quick as possible.