Yup, less one-shot, more novella. No regrets, this has been the most fun we've had in a while.

The one in which Peter signs some papers, and Tony has to talk about Feelings.

Living at Tony's was a breath of fresh air after the tension I was used to.
As long as I still went to school, I was left to do as I wished – within reason – and trusted to be responsible. Tony spent most of his time out of the house or holed up in his workshop, but he'd cleared a table for me in one corner, offered with a nonchalant wave of his hand and an utterance about keeping my space clean. I worked on my web shooters, asking questions as they arose, and valuing his input when offered, or else doing my homework. We spent countless hours in companionable silence, his music providing a comforting backing track, albeit at a volume more conducive to conversation than it had been that first night.

It was one such evening, three months into my time with Mr. Stark, when I shrugged off my backpack and dropped myself into my seat with a world-weary sigh, raising Tony's head from his latest indecipherable project. "Rough day, kid?"
"Penny this, Penny that…" I muttered, running my hands through my beloved hair. "You'd think they'd get the picture – but nope, they just think I'm a lesbian. Not that there's anything wrong with being a lesbian. It's just that I'm not one," I added, addressing the room as a whole as my cheeks began to burn. No way I'm discussing my sexuality with Iron Man… Gender is enough!
"Do you need me to talk to someone?" I blinked dumbly in response to the question, and he smirked. "I mean, if someone's giving you trouble…"
I shook my head slowly, sighing again. "I haven't even told anyone. I can't get mad about it, not really, if they don't know. It's just… Frustrating. I wish they could just know, y'know?" My fingers absently flicked a stray pencil across the table, sending it skittering to the floor and eliciting a wince from us both. "Sorry, Mr. Stark."
"Tony." He let out a breath as he bent, walking the discarded pencil back to me slowly, spinning between his fingers. "If you're… Struggling… I can tell whoever you need to know. Happy to help, if you want."
I hummed for a moment, then shrugged half-heartedly. "I dunno. I wish I could just change my name – there'd be no need to tell everyone then. It'd be done for me!"
Tony dropped the pencil in front of me, hesitating before he rapped his knuckles on the desk. "Leave it with me."
I felt my eyes widen, and I pushed the seat back as I leapt to my feet. "What… What does that mean?"
He wagged a finger over his shoulder as he turned, heading out of the room while I stood blinking, panicked, in his wake. "Mr. Stark? Tony! What do you mean?!"

"Kid? You up?"
I let out a soft groan, burying my face in my pillow. "No."
I heard the quiet huff of laughter through the door, and the hushed drag of material sliding across the floor. "Here. I got her signature. It just needs yours. I'll submit them in the morning, and then that'll be it. Peter Parker… Officially."
The last word sent me sprawling to the wood, scuffing my palms as I scrambled to my feet. "Wait- what?" I yanked the door open as my voice broke embarrassingly, jumping several octaves in shock.
Tony stood with his hands in his pockets, looking battle-weary but proud as he nodded at the forms I'd leapt over. "You can change your name at any age. But if you're under eighteen, your guardian needs to sign too. So… I got her to sign. You can do your part whenever – if ever – you're ready."
My mouth worked wordlessly, floored yet again by a display of kindness from this… Superhero. Another act that likely didn't mean much to him, in the grand scheme of things, but that meant the world to me. "I… I don't know what to say. How? Why? How?!"
He chuckled again, shrugging. "Hot chocolate's in the kitchen. I'll have cream and marshmallows." I noticed, for the first time – to my shame – that he was drenched to the bone, hair plastered flat to his head as rainwater ran rivulets across his skin. I opened my mouth to apologise, but he simply waved me off as he turned. "Cream and marshmallows!"

Tony appeared a few minutes later, just as I was finishing his desired additions, a towel slung over his shoulders, feet bare, and his hair still half-damp, sticking up at irregular angles. It was impossible not to smile. I'd never seen the inhuman man look so… human.
"What do you think you're grinning at?" he quipped, flicking a stray marshmallow at me with stunning precision.
"Is it raining?" I shot back, laughing as his mouth fell open in shock at my unexpected display of light-heartedness.
"We'll see how much you're laughing when I put you out in it, kid," he retorted when he recovered, rubbing the towel against his damp head before tossing it at me. I batted it away easily, feigning a yawn, and he chuckled, taking his seat and wrapping his hands around the mug. Tough as he was, he couldn't disguise the faint tremor in his grip as he let the heat leech through him, and a pang of guilt resonated within me that he'd been out in the bad weather for me.
"So…" I breathed out heavily, fingers resting on the form before me lightly. "How on earth did this happen?"
He shrugged a shoulder as he took a sip of his drink, wincing almost imperceptibly at the scolding beverage. "You wanted to change your name. I knew you'd never ask her, so I thought I'd do it for you. You're welcome," he added as I opened my mouth, and I blushed, my enthused gratitude dying before I could speak.
"She agreed?" I asked eventually, lowering my gaze to the paperwork. There it was, for sure – her name scribbled on the dotted line, thick and dark, the anger palpable.
"She… Conceded," he corrected, leaning back a little, a cocky grin turning up the corner of his mouth. I raised an eyebrow silently, and he shrugged again. "Greased palms are usually the only encouragement people need."
"You paid her?" I clarified incredulously, blinking dumbly when he nodded. "How… Why? Why would you do that? Why does it matter so much to you?" Why do I matter?
Tony kept his gaze on mine, silently calculating. I broke first, looking away as my palms became clammy, feeling his stare probe even as I took a vested interested in the swirl of cream on my drink. "You matter, kid. You're an Avenger, remember? We look after each other."
Something shifted inside me, swelling and ebbing in equal measure. I was honoured, of course. I was just a child, and here was this genius, telling me I was important. But… "Is that all I am? An Avenger? A teammate?" I fought to keep my voice measured, but Tony arched a brow at the perceptibly clipped tone.
"Isn't that enough?"
I started to respond as frustration bubbled, but caught myself. "... Yes. Of course. Sorry, Mr. Stark."
Tony sighed, reaching into the infinite depths of the pockets in his jogging bottoms, pulling out another sheet of paper, this one worn thin where it had been folded and refolded endlessly, long fingers tapping the document lightly. "You're not 'just' anything, kid. But you're especially not just a teammate – not to me." He pushed his chair back, throwing back the remnants of his drink without reaction, despite the steam still curling from the mug. "And you can call me Tony."

I sat peering into my cup long after it was empty, unfocused gaze staring through the line of powder congealing in the bottom while I scolded myself for my words. I was well aware of Tony's documented reluctance to let people close to him – pushing the way I had was akin to treason.
The papers he'd left lay under my hand, still folded, as engaged as I was in my own thoughts. It wasn't until a solitary tear rolled down my cheek that I drew myself back to reality, pulling the papers toward me with little interest.
New York State
Office of Children and Family Services
Application to Adopt

Adoption? Tony wanted to… Adopt me?

I barrelled into his room without knocking, taking pause at the incredible view sprawled before me. My own bedroom was comparatively modest, relatively nondescript – as far as a bedroom could be in Stark Tower, at least – when viewed next to the floor-to-ceiling window that took up an entire side of Tony's sleeping quarters. I'd seen some incredible views as Spider-Man, but this insight into the city I'd grown up in was irreplaceable.
Shaking my head – I could marvel at the sights another time – I pivoted wildly, eyes scanning the darkness for a sign of Mr. Stark.
"Did nobody teach you to knock?"
Turning, I held up the document, fingers shaking. "What is this?"
Tony took a long gulp from his stereotypical tumbler, sucking his teeth before replying. "Proof."
That stopped me, at least. "Proof?" I repeated, brow furrowing in a confused frown.
Tony nodded once, sitting at a sketching table tucked to one side, the soft glow of a worklight creating an aura around his body, and hiding his face. "That you're not 'just a teammate'."
Tears pricked at my eyes as he regurgitated my words with venom, and I recoiled from the blow. "I… I didn't mean to… That wasn't fair. I'm sorry."
He nodded once, fingering the edge of his glass, refusing to meet my gaze. "I've done my best, kid. I'm not always perfect, but-"
"You are, you-"
"Let me finish," he interrupted softly, looking up briefly to fix me with a stern stare. When I stayed silent, cowed, he continued. "I'm not always perfect, but I'm trying. This is unfamiliar territory for me, Peter. I'm gonna make mistakes, and say the wrong thing. And I'm not…" He huffed out a breath, scrubbing a hand over his face before standing, pacing before the window, his anxiety tangible. "My dad wasn't the sort of man who put any stock in talking about feelings. If I had a problem, he fixed it – or made it go away. I had everything I needed, everything I wanted, from a physical perspective. But feelings?" He shook his head, letting out an audible sigh. "Feelings are new to me. Pepper always said I have a heart, but it doesn't always feel like it. Sometimes I forget that not everything can be fixed – that people aren't machines. I want to fix things for you, Peter. And I want to be there for your emotions, too. I'm just… Still learning."
His speech left a heavy silence in its wake, punctuated only by the sound of flesh on bone as I chewed my lip. "I'm sorry," I offered weakly. "It was unfair to say that – especially when I already knew it wasn't true. You've done so much for me, Mr. Stark, and I shouldn't be so ungrateful."
Mr. Stark shrugged once, pausing in his paces. "I overreacted, kid. I'm not used to all this."
A flush crept up my cheeks, and I ducked my head in shame. "It's a lot. You don't… I don't expect you to keep me around."
He sighed, moving closer, discarding his now-empty glass on his bedside table – beside a half-drunk bottle of Jack. "Kid, you're stuck with me, okay? Whether we sign those papers or not, this is your home now, for as long as you want it. Nothing about who you are is going to change that, alright? So get used to it." He hesitated before tapping his fist lightly against my shoulder, his emotional discomfort tangible. "Now get to bed, Spider-Man. It's the middle of the night, and you have school tomorrow."