Simple observation told Nezu a lot about people and the world around him, he understood in the short amount of time he'd been alive that a majority of humans weren't worth his time as they were only following the established social construct made to preserve their species, and he saw little reason to entertain such people.
Human behavior was fairly easy to comprehend with enough time and Nezu hardly needed a fraction of it with his quirk, so for self-preservation, he gave as much as he needed to this societal contract for the autonomy he wanted, and to preserve it he put himself in a place of power in the superhuman society that he was a part of, hence his "one-man" campaign to become the principal of the infamous U.A.
However, that's not to say he didn't care for the children under his care, he absolutely did care for them, but he couldn't quite say he held any meaningful attachment to the hundreds of students that passed through U.A.'s doors, as in his experience, a good portion of them simply never interacted with him outside of his role as principal and rarely kept contact after they graduated.
Nezu was a being of logic having found it to be the closest thing to a friend he could feasibly manage, it wasn't that he hadn't tried but he understood and had long come to terms with the fact it was highly unlikely to be capable of any meaningful connection with another, human or otherwise.
Nezu's intelligence was, despite how many would think, frankly speaking, nothing more than a by-product of his quirk's nature, one that was the reason for his near-complete disconnect with others, even the few humans he spoke to with intelligence quirks had this... disconnection from him.
With all this in mind, Nezu hardly saw any reason to waste his time and energy trying to form something that simply wasn't going to be sustainable, hence why the majority of his connections were fellow intelligence-gathering heroes, undergrounders, or for mutual benefit.
Which is why Nezu found himself in his office hours before any of the students would arrive going over the multiple reports from his information networks with his breakfast and a cup of tea, this had become a mundane daily ritual for him.
In addition to reading the patrol reports he had multiple updated calculations of crime rates, spliced in were different scientific papers for some variety as he took it all in.
However, recently in the last week, Nezu had noticed something... odd in the data he was receiving, it wasn't anything major yet but the crime rates in certain prefectures had dipped by a minuscule number of a fraction, maybe less than 0.01% on certain days.
Now to most that number could be easily overlooked and Nezu had only briefly noted it the first time as he always did, but this number was not random as it floated around Japan in a consistent pattern, the number had also grown to surprising 0.15% from the first time he found it in September.
Despite the seemly innocuous nature of such a slight dip, Nezu understood too much about human behavior to think a crime rate change of five hundred percent (no matter how small the numbers were) was benign, the statistics just didn't match up. Humans were often creatures of habit and things didn't change that much in less than two months without some kind of outside influence.
Of course, there could be over a hundred reasons to explain the number but very few were compatible with the clear migration the number had, or the recent introduction of the lingering dropped rate of 0.05% in the last week, this change had to be man-made.
He highly doubted anyone would believe that theory out of hand, but some recent patrol reports and informants had gleaned something that had finally given Nezu solid grounding for his statistical oddity, a name had begun to be mentioned in various circles in the affected prefectures and such an odd name it was.
Deku-Sensei, meaning a worthless teacher, or a useless teacher.
From what little he scrounged up Nezu had strong reason to believe that this "Deku-Sensei" was some variant of an information broker, he had three reports from undergrounders (in different prefectures that weren't touching but a part of the migration pattern) where the hero in question overheard criminals suggesting going to Deku-Sensei if they needed to know something.
Another report from a different undergrounder who patrolled one of the affected prefectures, briefly described a conversation between a drug dealer and a client before they were both arrested, one where the client was giving details to the dealer on how to meet up with Deku-Sensei.
Having a new information broker in the criminal racket wasn't new and could be mildly... concerning depending on the information they were dealing in, that thought was crushed however when paired with the drop in crime rate because Deku-Sensei was obviously behind it.
Deku-Sensei might not just be an information broker like he previously believed but possibly some kind of puppet master hiding in the shadows and recruiting through favors, and "Puppet teacher" certainly made more sense than the other possibilities.
And today he got a report from one of his informants that was giving some evidence to believe his theory was a bit more credible than previously believed, the report itself was mostly comprised of just rumors as the informant wasn't as involved in criminal matters, but he did manage to overhear a small-time crook being told to go to Deku-Sensei if he wanted "help" with his problem, two weeks later the crook escaped from a hero in the top one hundred using his quirk in a previously unseen way.
This proved that Deku-Sensei was offering something to these people, whether it was just information or something else like strategies, either way, Deku-Sensei was clearly getting themselves a much larger hold in the Japanese criminal element, and that could be a threat.
Deku-Sensei was clearly establishing themselves and gaining ties all while hiding under the authority's radar so perfectly that the underground and intelligence-gathering communities were only just now finding breadcrumbs.
This was a minor issue right now, but Nezu could capably predict Deku-Sensei would only get bolder and might cause them serious problems in the future if left alone, so in order to properly deal with Deku-Sensei Nezu composed some carefully worded emails to his fellow information gathers to keep an ear out for any information on Deku-Sensei.
He also sent a similar email to the underground hero forums to message him if they come across anything involving Deku-Sensei, getting as much information about this mysterious broker was essential for proper capture of the individual, if necessary, there was still a lot of this Deku-Sensei Nezu didn't know and Nezu would always consider the unknown dangerous.
Finishing up Nezu cleaned up his office putting the papers away in their proper places, anything mentioning Deku-Sensei was stashed away in the "Special attention" drawer in his desk, then he checked the cameras for how many of his teachers were in and where.
It was only half an hour before school started so a portion of his staff were in the teacher's lounge and he made his way to see them about this possible issue, while a good deal of them weren't in the underground or intelligence community he saw no reason to exclude his staff in heroics from the loop, after all, it probably wouldn't hurt to also have a few limelight heroes on the lookout for Deku-Sensei.
He quietly entered the teacher's lounge and carefully set himself up on top of a bookshelf waiting a moment to see if any of them had the situational awareness to notice him before announcing himself, none of them did but it was always more entertaining to test them to see if any of them were getting better.
"Wonderful morning today isn't it Maijima-San?" He asked "popping" out of his spot and into Maijima's arms startling the many hero course teachers inside the room.
"U-uh yeah N-Nezu-San, g-great morning." Maijima nervously answered, careful to not move or knock Nezu off as he climbed down Maijima's body.
"Do you need something Nezu-San?" Bullet Jacker (Heroics department head and heroics teacher for the year) asked unfazed by the mammal's entrance as she continued writing on some documents, Nezu grinned back at her "Actually there is something I'd like to speak to you all about." He confirmed climbing onto the couch.
He could see some of them were dreading the news he was possibly going to give them, he would have begun to explain, however, he heard a familiar pair of footsteps heading to the lounge before the door was loudly opened at the door was a tired and highly irritated Aizawa who aggressively trudged through the room towards the coffee machine.
Despite Aizawa's... prickly demeanor, the human was one of Nezu's few favorites. After all, he didn't often find such an interesting contradiction in person, much less the pleasure of one willing to stick around as most humans he found interesting had the common sense to be wary of him.
"Tough shift Aizawa-San?" He inquired watching as the man proceeded to down a cup of coffee like a shot, Aizawa had been covering another underground hero's patrol route in addition to his regular duties last night, Nezu thought that perhaps he should excuse Aizawa from teaching homeroom to allow him more time to rest, he didn't like his favorites forcing themselves through unnecessary distress.
"Yeah, you don't look too good partner." Genji added having noticed Aizawa's more "frazzled" appearance like the others, Aizawa scoffed as he refilled his cup "I'd like to see any of you look better after patrolling an entire prefecture by foot in one night." He spat back pointing a threatening finger at the rest of the staff then downed his second cup of coffee.
Regaining some of his composure with the second dose of caffeine he ran a hand through his hair "Especially after that bullshit at the end." He grumbled rubbing the bridge of his nose, the last bit, in particular, getting Nezu's attention as the peculiar fact that it was Friday flashed through his mind.
*Ah, might Deku-Sensei perhaps still be in the area today?* he mused "Oh? Do tell." He implored choosing to speak of his theory either after Aizawa's debriefing or when school hours were over, whichever was more beneficial once he heard whatever happened at the end of Aizawa's patrol.
One Aizawa's eyes twitched, and he groaned "I was finishing up Scripture's route in Yaizu's red-light when a fight broke out between two gangs." Aizawa replied as he moved towards the other couch, Yamada and Kayama shared concerned glances, as would any person who has known Aizawa and his lack of self-care.
"Golly, sure must've been a tough fight all by your lonesome, you don't need to see Chiyo do ya Sho?" Yamada playful asked, already searching for injuries on the brunette though it was cleverly disguised by the blonde jumping Aizawa with a hug.
Aizawa huffed, passive-aggressively waving (read: shoved) Yamada off in retaliation, his annoyance having nothing to do with his friend's invasion of his personal space.
"That's the thing. I didn't have to fight anyone." He told him, making his exasperation of this fact clear.
"Oh~ did some naughty little limelight hero come along and spoil your fun by punishing those criminals before you could get a piece of the action?" Kayama teasingly asked, wrapping her arms around him from behind the couch, she too was also subtly looking for injuries which gained them far more points in Nezu's book, people genuinely caring for his favorites would always be a positive in his eyes.
Aizawa however was grumpy, as he always was when this sleep deprivation and physically exhausted and did not appreciate the woman's attention at the moment, Aizawa made this clear by briefly activating his quirk making his hair go straight into Kayama's face and she immediately pushed herself away, swiping at his floating hair.
"No." Aizawa coolly said ignoring the dramatic gagging from the woman as her hands brushed non-existent hair away from her face "Then what, pray tell happened to the two gangs?" Nezu pressed quite intrigued by the outcome of this situation, Aizawa shook his head "A kid gave them a pop quiz." He answered, his face in deadpan.
There was a moment of silence before Kan broke and asked, "Are you serious?" Aizawa's eye twitched again "No, I'm talking shit and yanking your chain." He said, voice dripping with pure sarcasm as he threw a glare over his shoulder at the Blood Hero, Kan reacted quickly throwing his hands up in surrender.
"Could you please elaborate what you mean Aizawa-San?" Nezu requested finding himself taken aback by the prospect, Aizawa groaned throwing his head back and pinching the bridge of his nose "I stumbled across the fight, wasn't that big, maybe... Around forty people in total," he began to lay out the details for them.
"So, I was about to call for backup when this idiot gets the great idea to intervene by throwing a glass bottle in the middle of the two, put themself between the groups, and launched straight into quizzing them... about pre-quirk history." He explained, resigned to how ludicrous he sounded.
"And that worked?" Maijima asked, rightfully incredulous "Yes, it did. They even answered his questions," Aizawa told them "And that's not even the craziest part, when he finished, he told them to take their wounded and fuck off, and they did." He exclaimed, practically hissing the last part.
"Seriously?" Genji questioned; he received a glare in return while Nezu hummed to himself "Perhaps the child had some kind of compulsion quirk that allowed him to order them around." He suggested as that would make the most sense and Aizawa only groaned, putting his head in his hands.
"Great... A pint-sized vigilante that can literally tell us to fuck off." He quipped getting up and going back to the coffee machine.
"Well, it's only a possibility, did you speak to the child?" Nezu inquired though Aizawa was more focused on getting himself a third cup of coffee "No, the problem child was one of the first to leave and was gone by the time the gangs cleared out, so I didn't see where they went." He grumbled, downing the third cup then started to brew up another pot of coffee, knowing Aizawa that fact was probably a blow to his pride.
"Aw, Sho. They were just lucky to get away." Yamada cooed throwing himself at Aizawa again, accidentally knocking his coffee cup out of his hands, the two were silent as they stared at the scattered cup on the floor "Hizashi!" Aizawa snarled rounding on the blonde before chasing the shrieking Voice Hero out of the room "How puzzling." Nezu pondered out loud as Baki cleaned up the ceramic shards.
First the oddity of Deku-Sensei and now a child capable of diffusing high-tension firefights with a simple quiz, one that might be capable of losing one of the best of the best in the underground heroics, how intriguing.
Well, if there was one thing Nezu loved, it was a puzzle and he had just been given two to play with.
Me the over-thinker, looking at the teacher's roster on the fandom wiki and realizing there aren't enough teachers: Well then, guess I'll have to make some more.
A couple hours later
Me: Meet Bullet Jacker and Baki, they'll get a proper introduction later.
Edit: I have a character key up on Ao3 now and its connected to story on Ao3 so it won't be that hard to find, I'd crosspost it but as its a list it wouldn't follow posting rules here, https archive of our works 49419613 this should work to help you if you search it the search bar.