The sensation of rushing liquid. It was a regenerative fluid. It helped in the healing of wounds and the reconstruction of anatomy. It was a necessary component in creating functional organic vessels, IE bodies, efficiently and perfectly.

Mosquito Girl. That was the name bestowed upon an insect-human hybrid. She was meant to be unrivaled regarding speed. Furthermore, through draining the blood of others, she'd achieve a greater state of being. In essence, Mosquito Girl would unlock her full potential through mutation and accelerated evolution via blood consumption.

Yet, unexpectedly, during Mosquito Girl's debut, she died. Her creator was monitoring her status and progress from their base of operations. Everything was going well, but then, Mosquito Girl disappeared. That's the only proper way to describe it. She simply vanished.

So, Mosquito Girl's creator, the renowned Geneticist Doctor Genus, decided the best course was to resurrect her. No S-Class heroes were in the city where she was sent for her debut. Additionally, no high-ranking A-Class heroes were in the area either. This mystery was too perplexing, intriguing, and worrisome to go unexplained. Thus, Doctor Genus cloned Mosquito Girl. It could be said that it was his specialty.

"The process is complete. Mosquito Girl will be conscious in a few moments." Dr. Genus informed...himself. Yes, as just mentioned, the man was exceptional when it came to cloning-related science. Logically, Dr. Genus would clone himself multiple times. What better assistants could a person ask for than themself?

However, for the sake of clarity, the REAL Genus stood before his reborn creation. Mosquito Girl was inside a specially-made tube-like apparatus. To simplify, it was a cloning machine. But it was capable of more genetics-related feats and wonders than just that.

But wait, you may say. Even if Doctor Genus could clone Mosquito Girl, how would she have her new memories? Wouldn't the clone be produced from preserved material that Genus would have readily available? That is a reasonable observation to make.

Remember, Genus was able to monitor Mosquito Girl's status despite her being so far from their headquarters. Although Mosquito Girl wasn't a cyborg, only one member of their organization was; Genus had each of his creations "tagged". Somewhere within their bodies, most likely their brains, devices were implanted that could transmit any data needed for research purposes back to base. Genus, with his vast intellect, was able to conceive a way to record and preserve the mental state of an organic lifeform flawlessly. So, when it came time to clone Mosquito Girl, they essentially "installed" her most recent up-to-date mind into the new body.

Now, before you plague yourself with the mental gymnastics of everything that's been said, please be mindful that this only concerns the known science of this world. Matters of the soul, true existence, and the persistence of life beyond death are irrelevant to the current situation. Were there now two Mosquito Girls? One alive, one dead? If there had been more before the last, did they also still exist in an unknown ethereal state? Again, don't dwell on it. We're talking about a big-boobed insect woman who drinks people's blood that was created by an egotistical madman with aspirations of becoming the new God. In conclusion, this is not the time for existential philosophy.

"Mosquito Girl." Genus spoke once he saw his creation's eyelids flicker. "Can you hear me? What happened? How were you dispatched so swiftly?" He asked.

A few seconds of silence passed since Mosquito Girl was still returning to herself. Then, suddenly, she jolted forward. Genus, not expecting such a violent reaction, jumped backward to avoid having her fall on top of him. The poor thing hit the floor with a loud THUD.

"IT HURTS!" Mosquito Girl yelled as loudly as she could. Her hands gripped her head as her eyes bulged in their sockets. "EVERYTHING HURTS! EVERYTHING! MAKE IT STOP! MAKE IT STOP! PLEASE! DOCTOR! MAKE IT STOP!" She cried and shouted, tears forming in her eyes.

"There's nothing physically wrong with her!" One of the clones exclaimed, informing Genus of what was going on. "It's all in Mosquito Girl's head! The memory of the experience!" He told him.

"PLEASE! MAKE IT STOP!" Mosquito Girl begged; every cell of her body felt like it was in agony. "I CAN'T TAKE IT! I CAN'T! IT'S TOO MUCH!" She carried on, succumbing to a sob.

Acting purely on instinct, Genus rushed to a nearby cabinet. Within its drawers and shelves were many different chemicals, medicines, and other scientific remedies or concoctions. Genus easily found what he sought. A syringe and a small bottle of liquid anesthetic.

Note: Doctor Genus's creations were the peak of genetic supremacy. Thus, regular drugs, even those used for surgeries or unsanctioned medical practices and experiments, would not affect any of them. That one bottle had enough potency in it to render half a city's population comatose. That was the MINIMUM strength required for ANYTHING that was meant to be used on Genus's creations.

By the time Genus made it back to Mosquito Girl, who was now in a ball crying like an injured child, he had filled the syringe with the mixture. Without hesitation, he plunged it into her. Yes, this is not the proper method for using a syringe. However, this was an emergency. Furthermore, any injury caused by this would be healed by Mosquito Girl's natural regeneration.

Over the next minute, the tearful and miserable insect woman slowly quieted. The bottle's contents did their job. Even so, this left Genus and his clones at a loss. As they stared at the now slumbering Mosquito Girl, who still cried in her sleep, they could only ponder one question.

What unknown entity was capable of inflicting such suffering? It couldn't be human. That was impossible. It had to be an unspeakable monster that even a mind such as Genus's couldn't conceive. Despite not being easily spooked, trying to imagine such a horror brought a cold sweat to his forehead.

Meanwhile, In A Ravine...

Light clouds of dust were blown across a barren wasteland. Among the vast emptiness stood two imposing walls of rock and stone. The space between these two walls was sizable. There was more than enough room for a number of activities to be conducted in this area.

Saitama, once he realized how insanely powerful he was becoming, searched for a place to monitor his strength's escalation safely. Thankfully, an odd consistency across every city was the environments nearby. Genuinely, no matter WHERE you lived, it was surprising how readily accessible empty plains were. You'd think there'd be more fights and large-scale battles happening in these environments, but no. Sadly, all destructive lifeforms in the world seemed to be naturally attracted to property damage and potential casualties.

But, as we know, Saitama was not one of them. He ensured to get proper control over himself to avoid any accidents. Thus, his "training grounds" were found. Isolated. Serene. Perfect.

Truthfully, Saitama never believed anyone else would use this location for the same purpose. Furthermore, He assumed that he'd never bring anyone here. But, as it was becoming a trend, Saitama experienced a bunch of "firsts" recently. Two of which stood with him in the middle of the ravine.

"Hmm..." Boros hummed as she looked around, dressed in her usual casual outfit. "Far be it from me to criticize you, Saitama. But I feel as though such an environment is a bit...drab." She commented.

"Unfortunately, my giant spaceship is in the shop. I can't train on Mars until it's fixed." Saitama jested, dressed in his hero attire.

"Ha, ha. Very funny." Boros mocked him in return. "Even if this is the most optimal location, especially given its proximity to City Z, we could do something to liven the atmosphere. Some paint would go a long way. Oh! Maybe some equipment, too." She suggested.

"That's assuming we don't destroy the place." Saitama started as he folded his arms. "I've only ever punched the air when I come here. I DID punch something once, and now there's a ravine." He shared.

"Sensei! You created this ravine?!" Genos questioned with a look of amazement. He was wearing the same kind of jeans and shirt as yesterday. The sleeves of the shirt were ripped away entirely, creating a nice, rugged aesthetic around the cyborg's shoulders.

"Again with the sensei thing..." Saitama thought, followed by a sigh. "Genos, we've gotta talk. I don't mind if you train with us, but do you NEED to call me sensei?" He asked.

"You're right! That isn't good enough!" Genos exclaimed, completely misunderstanding the issue. "From now on, I shall refer to you as master! That is far more fitting for someone of your calibur!" He decided.

In reaction, Boros threw her head back and laughed.

"What's so funny, Boros?" Saitama inquired, slowly looking at her.

"Ha-Ha...nothing..." Boros replied after wiping a tear from her eye. "I just enjoy watching the universe pay you back for ALL of those times where YOU thought it was OH so amusing to tease me about my speech." She explained.

"We call that karma, Miss!" Genos informed her.

...Oh! Right. You're likely wondering something, aren't you? Has Genos been educated on who Boros ACTUALLY is, as well as her crew?

Yup. There's seriously nothing more to it. Before coming to the ravine, Boros sat down with Genos and told him everything. He was more than okay with it. No, really. Genos didn't have anything to say or ask.

Granted, Boros did, as one would expect, an impeccable job giving the cyborg all the details. Even so, she was startled (yet relieved) by how accepting Genos was of her. Boros's already present fondness for him grew exponentially as a result.

"Oh. I didn't think humanity would conceive such a concept. That's my error." Boros said, glad to have this information. "Also, Genos, you don't need to keep calling me Miss. I'd much prefer if you'd use my name. I don't want there to be any awkwardness or formalities between us." She told him.

"Ignoring your position in the grand scheme of the universe, you are still as much of a superior to me as master is. I feel it'd be disrespectful if I didn't address you as I do." Genos explained.

"...He's not going to let that go, is he?..." Saitama wondered, dreading his new title.

"I appreciate that. Really. But I want us to get along without worrying about status or differences in ability. Please, this is something I must insist on." Boros responded.

"...Very well." Genos accepted, much to her delight.

"Thank you." Boros said, happy to see it work out the way she wanted.

"...Hey," Saitama spoke after a few seconds, trying his luck. "Could...you maybe also drop the master title? Saitama will do just fine." He requested.

"No!" Genos passionately refuted the idea, even going so far as to bow like before. "I cannot relent on this, master! I am your student! To not call you my mentor in a proper way would be unforgiveable!" He asserted.

Again, Boros was entertained by this outcome. She slowly turned to look at Saitama with the smugest grin in the universe.

"...Okay..." Saitama sighed once more. His tone was defeated. Despite knowing the cyborg for so little time, he could tell it'd be easier in the long run just to go with it. "Anyway, should we get this thing started?" He asked.

"Yes. We've had our fun, but now we need to get down to business." Boros answered, looking at the cyborg. "Genos, you're going to spar with me today. We want to see how good you are overall. The reason you are fighting me and not Saitama is that I have a more varied arsenal at my disposal. I can provide a unique and unpredictable combat scenario, thus forcing you to adapt as the fight goes on. When we've reached the end, I will then spar with Saitama. This will offer a visual demonstration that should also aid you in your training." She stated.

"Understood! Thank you for this opportunity Boros!" Genos replied.

With the conversation finished, Boros and Genos took their places opposite each other. Saitama would stand to the side and watch. He'd also be the one to give the go-ahead for the battle.

"Three...two...one...fight," Saitama told them.

In an instant, Boros disappeared. Genos, remembering how fast Mosquito Girl was the day prior, assumed this was also a feat of speed. So, he quickly scanned his surroundings. As assumed, Boros had moved closer to him. Specifically, she was directly behind the cyborg.

FWOOSH

Impressively, Genos spun around on only his left leg. With his right, he intended to deliver a powerful roundhouse kick to Boros's abdomen. Even though Genos was aware of her incredible durability, he didn't want to aim for her head. He'd do his best to aim for her center of mass to avoid causing her any discomfort.

"Aw, that's sweet, Genos." Boros complimented him, understanding the intent. Genos could only hear her voice as she remained unseen with her speed. Unsurprisingly, Boros avoided the attack. "However, in a fight, you need to do everything you can to end it as fast as possible." She said before suddenly appearing in front of him. "OBSERVE!" She shouted.

With an open palm, Boros struck Genos in the chest. However, like Saitama, she had control over her strength. She wouldn't accidentally damage Genos. If that were a possibility, this fight wouldn't be happening.

After being struck, Genos skidded across the ground, managing to remain on his feet the entire time. Despite not having lungs, Genos still felt as though the air had been forced out of him. He needed a second to recover.

"You okay?" Saitama called out. Boros reappeared as she stopped moving. Although confident she hadn't hurt their cyborg companion, she was still concerned.

"Y...Yes, master!" Genos exclaimed. "I was more surprised than anything else. I promise, I'm okay!" He assured.

"You sure?" Boros pressed. "If you need a moment, we can-"

"No!" Genos interrupted her, but not with an angry tone. "If I sustain any damages, I will inform both of you immediately!" He promised. "Additionally, in a real fight, I wouldn't get an opportunity to relax until the fighting is done! So, please, do not relent, Boros! Treat this like a real battle!" He requested.

"Hmm...that is very true. In an actual situation, your opponent wouldn't relent. They'd continue until you were reduced to scrap." Boros agreed. "Hence, you need to try and bring it to an end before it can escalate. That is why I said what I did before striking you." She told him.

"Of course!" Genos responded.

Taking a few seconds to asses Genos's condition to ensure he wasn't lying, Boros then continued the session. Instead of attacking him physically like before, Boros ascended to the sky. From here, she'd fill her fists with her power, which glowed with a vibrant purple light.

"Next, evasion!" Boros exclaimed before sending forward a barrage of spheres.

Even if Boros hadn't taken her time getting ready, Genos would've still been able to avoid this assault. The mere fact that the projectiles were visible was greatly advantageous. With excellent movement, the cyborg dodged and weaved through the barrage. Steadily, he was closing the distance between him and his attacker.

Suddenly, Boros smirked. Her latest volley hadn't hit the ground yet, meaning the spheres were still intact. Once Genos reached a certain point, Boros manipulated the orbs' trajectory. Now, her opponent was facing an onslaught from the front and back.

Yet, in an unexpected twist, Genos also smirked. He assumed that Boros would try something tricky like this. Now, it was his turn.

FWOOM

In an instant, several small ports across Genos's body opened and expelled intense heat. Visually, it looked as though the cyborg cast a ring of fire from himself. This circular wave of flames traveled swiftly. Although Boros's projectiles were well-made, they still couldn't maintain themselves when struck by a powerful counterattack.

With a window created, Genos shot up from the ground below. Fire propelled him upward as it shot from the soles of his feet. As the cyborg approached Boros, he threw both of his arms back.

"LET'S SEE YOU HANDLE THIS!" Genos shouted as his limbs suddenly shined with a bright orange light.

Before Boros could react, Genos used his thrusters to spin in the air. Remember, he was rapidly approaching her. So, when Genos released the building heat in his arms during this spin, it resulted in a volley of fireballs that covered a wide area. He planned to limit Boros's movement options while still advancing to perhaps land a physical blow.

Alas, this wasn't your typical mono-eyed brick house of a woman. Boros was THE mono-eyed brick house of a woman that all others aspired to be. Thus, she did the one thing Genos didn't anticipate. Boros, without flinching, took EVERYTHING.

The sky became orange. Boros and Genos became blackened silhouettes. Saitama, from below, squinted his eyes to try and see the result. Unfortunately, his eyes were still relatively normal regarding their vision capabilities. So, he needed to wait until the sea of light and flame dissipated.

Once the skies above were back to their normal blue hue, Saitama could view the scene. Genos, dumbfounded, was being held in the air by his shoulders. Boros, with another smug grin, gripped the cyborg so he wouldn't begin an unintended descent. As for Boros's condition, not even her clothes were burned. Although needing improvements to withstand Saitama's strength, when it came to everything else, her closet full of clothes was practically invulnerable.

"That was a clever maneuver, Genos." Boros praised her opponent. She used her left hand to pat him on the corresponding shoulder while maintaining her grip with the right. "Unfortunately, during this practice, you've failed to understand the very first lesson that having me as your enemy presented. When fighting someone with far greater resilience, you NEED to keep your distance. Unless you are certain that a different outcome will be achieved when you go all out, doing so, as you've just done, will lead you directly into your adversary's hands. In this case, quite literally." She told him, followed by a smile. "But again, that maneuver was a smart decision. If you weren't fighting someone of my level, you might've secured the win right then and there. But, if you don't, be quick to finish your foe before they can recover or surprise you in return." She advised.

"I will. Thank you, Boros. I will commit everything to memory." Genos promised, making her chuckle.

"There's no need for that. It's not like this will be the last time we spar. These points and many more will come up in every session." Boros responded.

"Hey!" Saitama called, getting their attention. "Remember me? I'm here, too!" He reminded them.

"Aww, is someone jealous?" Boros teased as she lowered herself and Genos to the ground.

"Jealous? Of what?" Saitama questioned.

"This beautiful, gorgeous, flawless specimen is giving her undivided attention to someone else~" Boros clarified as she and Genos were back on their feet.

In reply, Saitama looked around.

"Master, is something wrong?" Genos inquired, now doing the same. "Did you detect a monster? Is someone watching us?" He added.

"Nah. I'm just looking for the woman Boros was describing. I didn't think someone so impossibly perfect would be out here in the middle of nowhere." Saitama explained.

...

...

...

"...Saitama..." Boros began with an unnerving smile as she cracked her knuckles. "Are you suggesting that none of what I said applies to me?" She asked, slowly approaching him.

"I mean, it could. But you'd need to have a PRETTY big ego to think so highly of yourself. And I don't think that's a very-"

BAM

With an uppercut, Saitama was launched into the sky. Immediately afterward, Boros chased him. Genos, with eyes wide, dutifully studied the proceeding one-sided skirmish. Boros would unleash a torrent of blows and attacks on Saitama, who took them as casually as anyone could. If this first outing together was a preview of things to come, this trio had quite the future ahead of themselves.