We interrupt your regular broadcast to bring you, hopefully, the first of possibly many side stories which will either be partially or entirely cannon to the main story and all will vary in length, this one is entirely cannon
A human-sized Shukaku hummed to himself as he looked through the fridge, it's been a week since he made the kid, and the tanuki was pretty sure the kid's name was Izuku Midoriya, though he might be his jinchuriki Shukaku knew it was gonna be a while before Izuku would learn any jutsu outside of Shadow Clones but he already had a few in mind "Maybe he should learn the Rasengan as a way to teach shape transformation, or maybe Chidori since he's a sensor type and that could theoretically counteract the tunnel vision, maybe even Flying…" he muttered to himself as he closed the fridge, though, at the same time, he heard the squeaking of hinges, normally he would ignore it but be has to be cautious now When he turned around he didn't have enough time to moved out of the way of the pan flying towards him, though it simply just bounced off of his gut and clattered onto the floor.
Shukaku looked up and saw Izuku's mother standing across the kitchen, wielding another pan in one hand and her phone in the other "I don't know who you are or what you're doing in my home, but you better leave or I'm calling the police!" Shukaku raised his hands in front of him in an attempt to calm the defensive mother down 'Shit, now I gotta do this with an adult, their always more difficult to calm down than children, god I sound like a predator.' In an instant that felt like an eternity Shukaku carefully chose his words "Listen, ma'am, I know this looks bad but there's a perfectly logical explanation for this, you see your son ha-" the green-haired woman quickly typed the number for police at the mention of her son, but before she presses the call button Shukaku reacted using an ability he hadn't used in a while since the pot containing his sand was in the living space, but that didn't mean he didn't have access to nearby sand.
Shukaku relaxed a metaphorical muscle for the first time in a millennium, in a instant the tanuki pointed his arm at the woman, and suddenly, his hands detached from his wrist at high speed, turning into blobs of sand in their trajectory, one snatched the pan from the mother while other covered her hand and phone, preventing her from pressing the button. "Look I don't know exactly how you feel right now" Shukaku lied, he needed to get his jinchuriki's mother to calm down "But what I do know is that you need to settle down and let me explain" As Shukaku spoke the sand his body was now made of shifted, forming new hands from the stumps "Look, 'bout a week ago your son awakened his quirk and I'm it, kinda, I know it sounds crazy and sounds like I made it up on the spot, but I can prove it." he slowly manipulated the sand that was once his hand back to him, Inko's phone still in its grasp. Once it was within reach he grabbed the phone and placed it on the counter, the sand merging back to his body.
Inko jumped when the weird tanuki-like invader disappeared in a puff of smoke, she stood there, thinking about what to do, should she trust what the intruder said, that he was her son's quirk finally awakened, or should she call the police anyway? Inko shook her head 'I'll just bring my phone with me' She thought, a good in-between, she grabbed her phone and slowly headed for Izuku's room.
Izuku yawned as he wrote, he took a glance at the time on his phone '8:30 huh, I've been studying for eight hours' between studying for school and reading the pages of Shukaku's notebook the tanuki told the greenette to read, it's no wonder he spent so much time studying "Gah, Dammit." Izuku turned around and spotted a toddler-sized Shukaku on his bed "What's wrong, did mom almost catch you?" Shukaku turned around towards the freckled tween with a frustrated look on his face "No, my fat ass took too long searching through the fridge and you mother caught me, now you gotta reveal that you have a quirk early." Shukaku cursed under his breath, Izukuku's eyes widened as his heart rate increased slightly, his mother already found ou? But it's barely been over a week.
The tween jumped when he heard a knock on the door before his moms voice was heard through the door "Izuku, sweetie, are you okay?" Izuku looked at Shukaku who nodded knowing what they have to do, Izuku looked back at the door, he's got a lot of explaining to do.