One punch man! (Saitama x reader insert)

The Obsessive Madman

We looked back to see Genos stop out of nowhere. "I sense living beings deeper in. Master, two of them are approaching." We look down the hallway to see a giant monster holding a man.

"Oh, here we go! There are three. Which one is it?" The monster yelled.

"The one in the middle." The man replied.

"In that case, you don't need the ones on the left and right." Before I knew it, I was in the wall across from Genos mad as hell.

"Genos? (Y-Y/n)...? Hey." Saitama said.

"I am Carnage Kabuto. We got a combat experimentation room. Let's do this in there."

"You turned Genos into a piece of modern art and hurt (Y/n). Fight's on."

"Just a minute, who the hell do you think you are?!" I punched the monster right back and got out of the wall, brushing myself off. "Okay Saitama, kick his ass for me would you?" I slapped Saitama's hand as he walked into the room with the monster.

"Pretty big, eh? It's the biggest room in the facility. This is where they make us fight to test our combat abilities. Well then, let's start the killing." The monster said. Before they started, Genos got back up and put the monster on fire. "Still alive, huh?"

Genos ran up to him and tried to put him down, but got destroyed in one punch and landed in Saitama's arms. "He got me. Let me... take him." Genos whispered.

"Your face is all cracked. Don't push yourself." Saitama warned as Genos ignored him and shot him with fire again. The monster blew the fire back with his breath, giving Genos a perm. "Genos, you okay?"

"Yes." I looked back at the monster as he was looking me up and down.

"No you're not. Look at your head." Saitama turned back to the monster. "You've gone and gotten my hopes up. (Y/n), take Genos." I picked him up and flew away but before I could get far, the monster took a hold of me.

"Sorry Genos, but you need to live!" I yelled and threw him towards Saitama as he caught him and looked back worryingly.

"Well aren't you a cutie?" I leaned back from his smelly breath as he tried to kiss me.

"Have you ever heard of brushing? Your breath smells like hot ass on the sidewalk on a hot day." I plugged my nose as Saitama laughed at what I said. "Plus I'm taken by him." I point to Saitama as he got ready to fight again.

"Him? Fine, whoever wins gets to do whatever they want with you." I paled and glared at Saitama.

"Fine. Saitama you better win." I punched the monster again and flew next to the scientist. "What the hell were you thinking when you made him?"

"That I was going to prove people wrong." He replied lifting up my arm. "You're human, right?"

I pulled my arm away in disgust. "Yes I am. I got these powers from a crazy scientist with a syringe." I ignored his shocked face and watched the battle.

"Oh, I see it. I see it. You're supposed to be strong." The monster sneered.

"Don't disappoint me now. You're this place's ultimate weapon, right? You're clearly not the same as the guys from this morning. Look at you, just oozing with confidence." I smirked, hearing the confidence in Saitama's voice. The monster zoomed up to Saitama, but before he landed a punch, he saw what I was seeing my whole time with Saitama. Even though he doesn't show it, he's got a lot of power and bloodlust inside him to make anyone bow down in fear.

"Check." I yelled in delight as the monster flew all the way back towards the wall.

"What are you doing? Hey." I laughed as everyone was in shock.

"He just backed off? Carnage Kabuto?" The scientist said.

"So you did see it, right?" I yelled at the Monster as he looked at me then back at Saitama in fear.

"You bastard! How the hell did you get that strong?" The monster screamed leaving the room in silence.

"Saitama, you can't leave a question unanswered." I smirked as he got serious.

"So you wanna know too? Okay, fine. Genos, you listen carefully too." I walked next to Genos as the scientist walked up to Saitama. "Who are you?"

"I am Genus." The scientist greeted.

"Well, fine. Listen up. First, what's important is to make sure you stick to this intense training regimen. Listen, Genos. You just have to keep doing it. No matter how hard it gets. It took me three years to get this strong. 100 push-ups! 100 sit-ups! 100 squats! Then a 10 kilometer run! Every single day! And of course, make sure you eat three meals a day. Just a banana in the morning is fine. But the most important thing is... to never use the a.c. or heat in the summer or winter... so that you can strengthen the mind. In the beginning, you'll wish you were dead. You might start thinking, "what's the harm of taking a day off?" But for me, in order to be a strong hero, no matter how tough it was... even if I was spitting blood, and even if (Y/n) was worried and told me to stop, I never stopped. I kept doing squats when my legs were so heavy they refused to move. Even when my arms started making weird clicking noises... I kept doing push-ups. A year and a half later, I started to notice a difference. I was bald... and I had become stronger. In other words, you gotta train like hell to the point where your hair falls out. That's the only way to become strong. The guys that are fooling around with the "new human race" and evolution junk... will never make it this far. Human beings are strong because we have the ability to change ourselves." I snickered quietly to myself when everyone was shocked.

"...full of crap! That is nothing but standard strength training! And it's not even that intense! It's just a normal level! I--I have to get stronger. I didn't ask to study under you... just to hear jokes!-" As Genos finished his sentence, I slapped him and sent him flying.

"You don't know anything Genos! None of you do, so why the hell are you judging him?!" I looked at everyone with anger. "Come on, speak up! I want a valid answer!"

"B-Because no human should have that pow-" I think his name was Genius started.

"Then why the hell did you want his body?!" I screamed back at him, quickly shutting him up. "You think he got his powers like I did?! No! He got them himself! We both went through hell to get these powers, but mine wasn't as rough as Saitama's... at least he wanted his powers..." I took a deep breath, letting my anger out. Trying not to break everything, I silently walked up to Saitama and whispered in his ear. "(I'm gonna go punch something, once you're done cleaning up here, meet me at the supermarket.)" l laughed a little crazily, seeing everyone pale after looking at Saitama after he lowered his gaze. "Oh, and Carnage Kabuto." He slowly looked over at me terrified. "If you're still cocky, fight him. I dare you." After seeing his agitated face, I walked passing the scientist whispering checkmate by his ear before leaving.

-timeskip-

"GODDAMMIT!" I punched the ground out of frustration causing an earthquake. "Why do people like them piss me off so goddamn much?!" After venting out my anger, I went to the supermarket with the sale and bought some food humming to myself.

"That was one powerful earthquake!" I turned around to see Genos and Saitama walking up to me.

"Oh that wasn't an earthquake, that was (Y/n)." Saitama said back to Genos. I wave cheekily as his eyes widened in shock. "Never get in her way when she's angry."

"I'll remember that." After we got a bunch of stuff, we said goodbye to Genos and walked back home.