Chapter Text
Nedzu was shocked to hear the doorbell to UA rang nearly a dozen times. He assumed it was just some reporters, but after a dozen or so rings he finally went to the gate to handle whoever wanted to annoy him at an ungodly hour than is 2:00 in the morning.
Nedzu put on his usual pokerface, so the press had nothing to hold over his head even if they caught him in a bad mood. Afterall, blackmail was his thing. Nedzu's smile faltered when he saw a five year old green haired boy just standing there with what appeared to be a notebook and a letter in his hands-
"Oh dear," Nedzu figured this boy may have gotten lost or was even being followed by a villain. So Nedzu ushered the boy inside and closed the gate. If this kid was about to be kidnapped, well the rat demon wouldn't allow it. Once inside, the boy asked Nedzu something-
"A-are you Principal N-Nezu?" The principal nodded. "M-mommy said to g-give y-you these," The boy handed Nedzu the notebook and letter. "The n-notebook is m-mine. I-I don't know wh-why mommy left me here."
Nedzu looked puzzled for a moment, before flipping through the notebook. It was impressive, such the technique could use some work, but overall very impressive analysis. Then the rat god opened the letter, which had been addressed to him and had no return address-
Principal Nedzu of UA,
If you are reading this, then my son has reached you. I couldn't keep him safe, a villain wanted his analysis. He has an IQ quirk, called: 'Analysis'. I need you to keep my baby safe. I wish I hadn't failed as a mother. Don't bother looking for me, by now I'm likely dead. Please, I beg you, as a mother, to keep my little Izuku safe.
-A Worried Mother
Nedzu feared the worst for this boy's mother, but he could search for her. One, he had no name nor appearance, and two none of his fellow teachers were awake- Well besides Aizawa, but he was busy tracking down a massive drug ring.
Nedzu turned to the boy, and smiled warmly. A smile the rat god hadn't had for a long while-
"Izuku-san," The boy looked towards the animal with curiosity. "I am Nedzu. Your father."
Aizawa had a long night. He expected Nedzu to throw a lot at him, even though he didn't have a single student this year, he still had other work to do. He didn't know why, but he had a bad feeling as he approached his boss's office.
Aizawa's jaw fell open. He expected anything from extra paperwork to helping Nedzu hide another body, but not a green haired five year old drawing pictures as Nedzu watched. The rat god turned to Aizawa as he heard the door close-
"So into kidnapping children now?" Aizawa deadpanned. Nedzu simply laughed at- what he assumed- was Aizawa's attempt at making a joke.
"No, young Izuku here was left on the doorstep of UA at 2:00 this morning," Nedzu gestured his paw towards the young child.
"So why don't you just drop him off at the police station or orphanage?"
"That would be because a letter from his mother detailed that he is the target of some villains."
"WHAT!? HOW CAN YOU SAY THAT SO CALMLY!?"
"Because I have decided this boy is under my and UA's protection," Nedzu smiled, as he clapped his paw together. "After all, no one has ever broken into UA's security! The boy should be safe here."
Aizawa sighed, as normal his boss made a logical and undebatable point. However, Aizawa still wouldn't put it past Nedzu to kidnap a child and cover it up with a story like that- "Can I see this letter, Nedzu?"
"Of course!" The shocked Aizawa, as Nedzu handed the letter over to him. Aizawa had seen Nedzu's handwriting and forged signatures enough times to see this wasn't his handwriting- erm- pawwriting. "Do you see the importance now?"
"Yes," Aizawa said, tirely.
"Papa!" The green haired boy smiled. "Look what I drew!" Nedzu and Aizawa looked at the adorable picture of Nedzu, Izuku, and what appeared to be a green eyed and haired woman- "It's you, me, and mommy!"
"That's wonderful, Izuku," Nedzu smiled. Aizawa raised an eyebrow- "Papa?"
"Ya, Sir Nedzu is my dad!" Izuku smiled, brightly. "Mommy left me here so I could meet him and live with him! She said, Sir Nedzu would keep me safe! And Sir Nedzu said he was my father!"
"I see," Aizawa said calmly, as he glared towards Nedzu.
"Papa? Is this Uncle Zawa?" Nedzu nodded, with a smile. Aizawa was shocked, he'd never seen a genuine smile on his boss's face. Only cold, calculated ones. Aizawa sighed-
'If this is what it takes to stop rats from becoming the dominant species, so be it...' The glance between the two teachers proved Nedzu knew what Aizawa was thinking. Izuku spoke, getting their attention-
"Papa?"
"Yes, Izuku-san?"
"Why did you and mommy spit up?"
"What?" Aizawa asked.
"I n-never knew you until l-last night?"
Nedzu smiled softly- "Me and your mother didn't understand each other that much. But trust me it has nothing to do with you. Now why don't you go ahead and go to sleep. You've been up all night, Uncle Aizawa will go tuck you in, in a few minutes."
"Okie!" Izuku ran off towards Nedzu's personal room.
"So are you actually his father... or...?" Aizawa was cut off by Nedzu.
"It was an experiment."
"What?"
"I offered my DNA as a sperm donor to a infertile couple. I had to see if it was possible for interspecies breeding to take place in the age of quirks."
"How did it even work!?"
"The hospital I sent my donation to has a nurse who can change DNA slightly. Anything from blood type to organs. In the past, people needed a specific donor of blood or organs, otherwise their body would reject it and kill the person. However, I wished to see if her quirk could make it possible for interspecies. So I sent in a request saying my donation was from a person with rare hereditary diseases that must be altered greatly or the baby made have diseases that could cause the mother or child serious health problems. Turns out, it worked."
"Great," Aizawa said, sarcastically. "So you sent in your DNA for a child, to use a random infertile woman as a- pun not intended- lab rat."
"Yes."
"You don't even deny it," Aizawa shook his head. "I don't know what I expected. I hope you know taking care of a child is hard work."
"Of course, Aizawa," Nedzu smiled. "That's why I have the help of you and all the UA staff. Of course we are gonna keep my little experiment underwraps. Ok?"
"Like I'd tell those vultures about this kind of scientific discovery. They'd eat us, the nurse, and the green haired problem child up alive. Now I'm gonna go check on the kid. I'm guessing your gonna use this time to come up with an excuse and tell the other staff?"
"Perceptive as always, Aizawa."
"Whatever," Aizawa growled, as he left to find the child. The child was already in Nedzu's bed reading a book. "Hello, Problem Child."
"That's a funny nickname, Uncle Zawa!" Izuku giggled. Aizawa grumbled a bit, but smiled slightly, as he walked over to Nedzu's bookshelf.
"So what story do you want to read? Marry had a little lamb? The Three Little pigs? Red Riding Hood?"
"What about that big book- Cackulis?"
"You mean Calculus?"
"Ya that!"
"That's a high school level math book, though?"
"That seems a little simple, Uncle Zawa! Mommy always read me college books!"
"I see," Aizawa shook his head. 'This is definitely Nedzu's son.' "Well, we only have high school level books."
"Oh, that's okie," Izuku seemed a little upset, but accepted they didn't have any higher level books. Izuku fell asleep not long after Aizawa started reading, whether it be staying up all night, a boring read, or a mix of both Aizawa will never know.
Aizawa smiled, as he stood up-
"Goodnight problem child."