He knew who he was and where he lived.
After Batman left, Percy got a pizza before heading home. He arrived at an empty house since his mom was working on making a good impression at her new job. As is his routine, he ate and cleaned up after himself, then did the chores to make his mom's life easier. After that, he did his homework, which was not much due to the school year just starting, and then he watched TV for a while, trying and failing to keep his mind off the dial on his wrist.
He started fiddling with it when he realized the dial wasn't stuck anymore, and he kept dialing the first number in the sequence before deciding he shouldn't, over and over again. That went on until he decided to shower, but when he went to his room to get his towel, he was startled by the imposing figure of Batman standing there.
"W-what the hell?!" said Percy. "How'd you get in here?! Wait, how'd you find me?!"
"I'm Batman." he said, and this time Percy saw a smirk on his face before it returned to its usual stoicness. "Did you mess with the dial?"
"COUGH. Not really. Just one turn. A few times." said Percy, only to be met with silence and an intense stare.
"What do you want to do?" asked Batman after a few seconds, catching Percy off guard.
"What do you mean?"
"The dial is bound to you, for whatever reason. As far as we know, neither you nor an outside party can remove it. As for the dial itself, I scoured for information and found nothing. No mention of it anywhere. It seems the only ones who know about the dial are you and I." he explained. "As long as it isn't dialed, with a sequence only you and I know, it's just an odd-looking watch. No one will ever know. You can keep it with you and live your life. Today would be only a fleeting memory."
"Or?" asked Percy.
"What do the numbers 4376 spell?"
"Spell?" Percy said, thinking about the letters assigned to each number on the dial and going through possible combinations until one fit. "4376. H E R O."
"Hero. You could use the dial to do some good. We don't know the full extent of the dial's capabilities, but even if you can only transform into Pixie, it'll be useful." said Batman.
"A-are you asking me to be a hero?" asked Percy, swallowing to moisten his throat.
"No. Hero is a title. I'm asking if you want to do some good."
Percy didn't know what to say to that, or rather, he knew what he wanted to say, but he had to think about it rationally. If he were to accept Batman's offer, his whole life would be turned upside down. He would probably have to fight villains and bad guys and put his life on the line as he did so.
More important than that, however, was his mom. He wouldn't want her to worry about him, so he would have to keep it a secret, which meant lying. He hated lying to his mom, but if it was between that and her worrying at all times of day, it would be better to lie.
Another thing he had to consider was both his and his mom's safety. If he made enemies who wanted to hurt him, and they found out who he was. The thought of his mom getting hurt because of his choices nearly overpowered his desire. Nearly.
Just like earlier when he was reluctant to hand over the dial, he realized he could do good with it. He could help people by stopping the bad guys who wanted to destroy the world or whatever their plans were. And he hated to admit it, but a small vainglorious part of him thought it would be cool to be a hero.
'A hero.' thought Percy before looking Batman in the eyes, determined. "I'm in, but we have to keep it a secret from my mom."
"Keep what a secret? Who are you talking to?"
Hearing his mother's voice, Percy turned around and saw her making her way to his room while looking at some mail. Sally Jackson was a strikingly beautiful woman with a perpetual warm smile on her face and sparkling blue eyes. She had long brown hair with a few streaks of grey intermingled that didn't make her look old but enhanced her beauty.
Before he could say anything, he saw her look up and go wide-eyed, clearly having seen Batman.
"Percy. Why is Batman standing in your room?"
"Uhh, he uhh, saved me?" said Percy.
"Your son recently came into possession of a device that we believe would be dangerous in the wrong hands. Unfortunately, we are unable to remove it from your son's wrist. Therefore, we feel the safest way to proceed would be for Percy to receive proper training to use the device to its fullest potential." Batman explained, not beating around the bush. "Naturally, if he accepted, the next step would have been to ask for your permission, seeing as he is a minor."
"What he said."
"... I see. Percy, can I see you in the hallway for just a sec? Excuse us, Mr. Batman."
"Of course." said Batman.
Percy then awkwardly followed his mom out of his room into the hallway, where she closed the door.
"What the hell is going on?!" she whisper-screamed.
"I-It's like he said." said Percy, showing her the dial on his left wrist. "See? This is the device."
"So take it off!"
"I can't." he said before showing her that no matter what he did, it would not budge.
"He said it's dangerous! What does it do?!"
"When I dial a certain number sequence, I transform."
"Transform? Into what?"
"..."
"Percy, what do you transform into?"
"We're not sure if it's the same every single time, but when I used it, I transformed into ... a half-fairy girl." said Percy, slightly embarrassed at saying it out loud.
"A fairy girl?" she asked, surprised. "So ... you weren't my son, but my daughter?"
"Not exactly. It's more like I switched bodies." he said, trying to make it sound better than it was.
"Can I see?"
"You want me to dial the sequence?"
"Yeah. I'm curious."
"W-what about the danger? Aren't you worried about your son's safety?"
"You were fine once, you'll be fine if you do it again." she said, waving him off. "Now, come on. I want a daughter for a little while."
"Mom!"
"Percy, I heard you say you wanted to be a hero. You've always had such a big heart, even as a little boy. I love that about you." she said, cupping his face. "I've been preparing my heart for the day you told me you were going to go off and be a police officer or a firefighter or something that helps people but puts you in danger. This is in that same vein. Maybe a little more intense, but still."
"Mom." Percy said, full of emotion.
"You're such a thoughtful kid, I'm sure you've already considered that you may be putting me in harm's way or that I'll worry, but no matter what you do, where you are, or what age you are, I will worry. Because I am your mother, and I'll support you no matter what you choose to do." she said, kissing him on the forehead.
"I love you, Mom." Percy said, hugging her as he wiped a tear from his eye.
"I love you, too, Percy."
They hugged for a few seconds before moving apart, both of them wiping a tear from their eye.
"Now, let me see you as a girl." she said, lightening the mood.
"Fine, but Batman should probably see." he said, opening the door back up, Batman still standing there. "She wants to see before she signs off."
"No deal otherwise." she said.
Batman stayed silent, ruminating on the demand before he nodded in assent.
"Here goes." said Percy, taking a breath before dialing.
A blinding light consumed Percy's vision before he felt his body changing. Like before, he felt his stature shorten, his frame slimmed in some parts and expanded in others, and his hair grew longer. Unlike before, he also felt his bones become sturdier, heavier, as if they had become metal. His outfit again became a blue and yellow form-fitting suit, but this time, a mask with long black ears appeared, leaving only his mouth uncovered.
With the transformation complete, new information entered his mind, shortly followed by an irresistible urge.
"I am Wolverine[1]!" he shouted, his voice, once more, female, but this time it carried an edge, making him sound almost feral.
Before he could say anything else, he was hit with an overload of sensory information that made him clutch his head. His vision had improved drastically, going from 240p to 4K, his hearing had improved to the point he could hear a couple arguing a couple of streets over, and to top it all off, his sense of smell was picking up the faintest and most vile smells.
"Percy!" said his mom, worried.
"I'm okay." he said, using the information he was given about his abilities to rein in his senses to a tolerable level. "Just getting used to the body."
"How so?" asked Batman.
"One of the abilities/capabilities of this person is very, very acute senses. I got hit with an overload of sensory information I wasn't used to." he explained.
"I see."
"Are you okay now?" asked his mom.
"Yeah. I dialed it down."
"Phew. Good. Then I won't feel bad about this." she said, breathing a sigh of relief.
"Feel bad about wh-" he said, only to be interrupted.
"Oh my god! You're a girl! I've imagined this so many times!" said his mom, her voice loud enough to make Percy wince thanks to his superhuman hearing.
"You've imagined me as a girl?" asked Percy.
"Of course I have. No offense, sweetie, but I've wondered what it would be like if you were a girl instead."
"Now why would that hurt my feelings?" mumbled Percy.
"Oh, stop it. Every parent does it. I've also wondered what it would be like if you had been a twin, two boys, two girls, and one of each." she explained.
"But I'm the best case scenario, right?"
"Uh-huh." she said, not sounding completely sincere. "Now, take off your mask. I want to see your face."
Rolling his eyes, Percy removed his mask, revealing a pretty yet subtly dangerous face with green eyes.
"Oh my god! You're exactly what I imagined you would look like as a girl!" she said, grabbing his face and inspecting it. "Can you stay like this forever?!"
"I'd rather not." he said through squished cheeks.
"Oh, come on, you've already lived 14 years as a boy. Give me a year with you as a girl."
"Even if I did want to, which I don't, I'm pretty sure this thing has a time limit." he explained.
"How long?" asked Batman.
"I don't know, but about an hour after I got home, I realized the dial wasn't stuck anymore, so I'd guess it has a limit of an hour." said Percy.
"What other abilities do you have?" Batman continued, and this time, Percy's mom stayed quiet, seeing that this was important to take note of.
"I have an accelerated healing factor, superhumanly acute senses, superhuman agility, reflexes, durability, stamina, strength, and speed. I also have retractable claws, two in each hand and one on each foot, and my entire skeleton is laced with a metal called Adamantium." he explained.
"Adamantium?" asked Batman.
"It's a near indestructible metal, according to the information I got." explained Percy, deciding to extend the claws to show off the metal.
As he extended the claws, he felt a pain unlike anything he had ever felt before. The claws were housed beneath the skin and muscle in the forearm, and unsheathing them caused the skin to tear and bleed. Already, the pain of unsheathing them was enough to make him want to scream, but then he felt the wounds regenerating, and with that came more pain.
"Argh!" he shouted, falling to his knees as the claws popped out through his knuckles.
"Percy!" shouted his mom.
"What happened?" asked Batman, a little more urgency in his voice.
"The claws have to tear through my flesh to be released." he said, gritting his teeth from the lingering pain, but thanks to the healing factor, it went away quickly. "I felt the pain from them being unsheathed and from my wounds stitching themself back up."
"You maim yourself to release those things?!" she asked.
"I would be if I didn't heal." he said, standing up and showing her his knuckle. "See. No wound. It's just momentary, and then I heal. Really, really fast."
Now that the pain was gone, he could admire the Adamantium claws, and he had to admit, they were beautiful. They were a foot long and slightly curved, gleaming silver. Swiping them at nothing, he could feel no resistance from the air, letting him know they were very sharp.
Out of curiosity, he casually swiped his claws at the door and managed to cut halfway through it, only because he stopped himself. His jaw dropped at how easy it was to cut through the door, but before he could admire it some more, he felt his mother pulling his ear.
"Ow!"
"Percy Jackson! What the hell do you think you're doing?!" she said.
"It was an accident! I didn't know it would do that much damage, I swear!" he said, trying not to move so she wouldn't pull more.
"You're paying for that!" she said, letting go of his ear.
"I'll pay." said Batman.
"No." she said firmly. "He damaged it, he'll pay. Your allowance for two months should be enough to pay for it."
"Yes, ma'am." he said, quickly agreeing.
"Now, put those things away before you damage something else."
"Yes, ma'am." he said, sheathing the claws.
Just like when he extended them, he felt the pain from them tearing through his skin as they retracted, but he was mentally ready and gritted his teeth to bear the pain.
"How detailed is the information you receive about your transformation?" asked Batman.
"Just a rundown. I received the name and alias of the person I transformed into, along with their power/abilities and a general idea of how to use them. I also get some other information."
"What other information?" he asked.
"Well, like with Pixie/Megan Gwynn, I know I'm something called a mutant. Though in the case of Pixie, she is a mutant and fairy hybrid." explained Percy.
"Mutant?" questioned Batman.
"Yeah. My guess is a mutant is just what it sounds like: humans who have a genetic mutation that granted them a power/ability/series of powers." Percy explained his theory. "But that's just a theory."
"What about your outfit? You wore a similar one when you were Pixie." asked Batman.
Both times he had transformed, his outfit was a blue and yellow form-fitting suit with a belt that had a buckle with a red background and a black X. There were small variations between the two, but overall, they were very similar, like a uniform.
"No information about it, but it looks like a uniform."
"Yes. It does." said Batman, going quiet for a few seconds. "Turn back."
"Wait." said his mom, stopping him from dialing. "Don't you want to know how long the transformation lasts?"
"You just want me to be a girl for longer, don't you?" said Percy, seeing through her.
"What? Of course, not. I brought it up for the sake of having the full picture on the device." she said, looking at Batman. "Wouldn't you agree?"
"I would." agreed Batman, a tiny smirk on his face.
"Great!" she said, clapping. "Now, if you would, please follow me. Uh- what's this person's name?"
"Laura Kinney." said Percy.
"Beautiful name. Now, Laura, please follow me. I have some clothes I want you to try on." she said, grabbing hold of Percy before he could decide to run away.
For the next fifty minutes, Percy was forced to be his mother's dress-up doll, wearing clothes from her youth that she had stored away. It was a very odd experience for Percy, but he saw how happy she looked and decided to suck it up. He kept telling himself he was having a very realistic nightmare, and that helped him get through it.
Just as she was about to make him change into something else, a blinding light erupted, and once it faded, Percy was back. The only thing was, he was still in his mom's clothes while his clothes were where the uniform he took off was.
"Aw, man." she said, putting back the clothes she had already picked up. "Well, it was fun while it lasted. Go change before you stretch out my clothes."
With a sigh, Percy stiffly walked to his room so as not to rip his mother's clothes and quickly changed into his clothes before walking to the living room, where Batman suddenly appeared. While Percy was forced to play dress up, Batman left to fight crime, having said he would return when the hour was up.
"It was an hour, then." said Batman.
"Yeah. One hour time limit." answered Percy before messing with the dial and seeing that it was not stuck like last time. "Seems like it's an hour limit even if you undo the transformation."
"Good to know." said Batman. "Is your answer the same?"
"..." Percy said nothing, thinking about it again, but he found he had the same answer. "Yeah. It's the same."
"Ms. Jackson?" said Batman, looking over Percy's shoulder at his mom.
Looking at her, Percy could see she was worried, but at the same time, she looked proud.
"You promise to take care of him? Because if something happens to him, there'll be hell to pay." she said.
"He'll be trained with others." said Batman, intriguing Percy since that was the first time he had heard anything about there being others. "He'll be taken care of. I promise."
"Okay. If that's what he wants." she said, smiling.
"Thank you, mom." said Percy.
"Tomorrow, after school. Meet me in the alley where we met." said Batman.
"Got it."
"Ms. Jackson."
Batman nodded at her, and with a flurry of his cape, he was gone, leaving both mother and son in awe.
"Are you going to learn how to do that?" she asked.
"I hope so."
[1] Laura Kinney, but the Krakoan duplicate, which means it's her but with a full adamantium skeleton.