You pull off the tag, which burns away in blue fire to nothing as you drop it in surprise. Gingerly examining the lack-of-residue, a slight headache pushes you to stand up...you grow the beginnings of antlers?! Looking in the mirror, you watch as little velvety brown branches sprout from your head. They're rigid, but softer than expected and a bit furry, deer-like. They're not even that high or wide, forward-facing nubs-and-bumps that you palm over incredulously. Surprise inexplicably fades, and you snort at your reflection like this mildly-horrifying change was supposed to be cooler. Your face looks a bit more whiskery in the mustache area, but nothing abnormal. A few rough spots like elbows and knees look a bit more scaly and something blue under the skin, like humanity is just an affectation or a covering. What's inside you...that feels different.
A wet, dripping energy stirring within you, like you're about to melt into water and... insight. A forgotten draconic essence, used to become a creature capable of escaping attention, swirling down from your head into your bodily core. Like remembering something you'd forgotten. It was less that no-one would notice you, and more that you could make yourself beneath notice! You had power over mirages and self-transformation, but doing much else was magic you'd have to...figure out. Channel. Do stuff. All this came to you instinctively, tumbling over cycling symbols you didn't really understand yet. It was like you were water in a jar, but whenever you were poured into another vessel you gained more water instead of less. Like the air was...
You step up, off the floor, hovering like a dream and about to dance as the dragon flies...and promptly let go of something to become a splashy mess. You melt, becoming a blob of water that saturates your clothes and splashes about the bathroom! In something between confusion and panic, you flop back together like a puddle congealed, and resolidify as yourself sitting atop your clothes with the same modifications you'd just experienced. A bit of blobbiness, and the horns melt back into your head, and your elbows look about right again, and you heave like you were going to splash yourself everywhere. Okay, that was...whatever that was. You managed to surge upright like a water fountain, clumsily condense back into human, and...steady yourself from there. Steady, steady, don't drop, and...easier. Like being a solid human, except consistency was only politeness that could be discarded with the right rudeness or force.
Floating up again is like levitation, though it's a bit faster to step and wave in the air manually as if swimming or climbing an incline. It's funky, being able to touch the ceiling and turn into a watery mess. You stretch yourself around a bit, becoming wiry and lean before collapsing down into a dwarf. Weird, weirder, and...oh. You could store your mass or weight or whatever this was water...inside yourself or more abstractly or something? So you had a bit of flex as to how big or how small you were, and weight included. Funky. Not enough funky-spirit-water-mass to become a giant dragon yet, but definitely enough to pass as unchanged. Or very changed. A bit of stretching and pointing makes you look like your normal self again, the watery inside filling a niche you'd never known was empty or weak with newfound strength. A lot easier to pick up a bunch of random bathroom miscellany at once, tendrils and bubbles of water-self feeling a lot stronger and more graceful than you were before. Your water flashes from water-y to a bizarre scintillating rainbow as you examine possibilities of color and consistency. Well, only for you to consolidate it back down to water-normal colors and then make it both texturally and visibly like...you. That is a bit creepy so you make your main body look you-ish and all the extensions or flopping-about bits a more water-looking faintly-bluish transparent.
Speaking of miscellany, you needed a revenge plan. Something about the dragon power shoved within you made you feel...vengeful. Her smashing your phone was rude enough you were going to get back at her in a fight, somehow. Or at least embarrass her instead, since magical girl stuff could be cool and played off as video editing over cosplay. Her bizarre flippancy at some seal or unlocking (or...seal of unlocking? You didn't get it) was ridiculous. Curses of misery, and yet you felt anything but. Maybe she'd have less misery going on if she stopped making people miserable, and you sure weren't gonna stop the cycle of violence yourself. Six days and she's already gotten herself on your hit list, really. You should probably care more about her dickery-yet-grace combo being enough to make you hate her that fast, but maybe it was magic or something that everyone else was just going along with her. Or you're an incel, you're pretty sure you're beneath attention for the girls enough for it to be your fault somehow.
But screw recanting. You should probably get ready for school, even if you were going to make good on her desire for you to be invisible somehow. Showering is an interesting experience, the water flow something you can control, but not 'you' sensorily unless you claim it as you...or let go, as you could when using the bathroom. Accidentally-then-intentionally gaining a few pounds in more-literal-than-usual water weight, you figure out how to adjust that gained weight from fat into reasonably-coherent musculature and leave the shower looking good.
You reconsolidate, toss your clothes back on (a bit tighter, but not uncomfortably), smirk evilly and...go invisible? Your reflection vanishes in the mirror, and while you can sort of tell where your body parts are by proprioception you are so see-through it was definite that you'd vanished. You can barely make out your clothes as the ever-so-slightest air distortion tops, and only because your sight feels a bit better than usual. Or maybe it's not your sight alone? Oh. So that was how the illusion part worked. With a newly refined sense that is...sort of like sight but even with your eyes closed, or the feeling of vitality or creepiness when looking at an emotively-charged scene, you can definitely make out the energy within you...and muffle its external expression. You are the hidden dragon, crouching tiger not necessarily included.
Your parents are the generally detached rich person type: when you walk downstairs a few minutes later visibly, you almost instinctively extend something to be sure they won't ask questions. And yet it works. They accept the request for a new phone without so much as asking why your existing one is broke. (To be fair, they were the kind of people who might have not cared or made their own assumptions anyway). It's like you can swap between everything you do being normal and not to think about it too hard, everything you do being unnoticed until you let go, and slash or...whatever they expect you to be doing is being done and that's you instead? That last bit you apparently will sort of release a water blob to play out what strictly needs physical intervention to handle, and the rest is just treated as being done by a normal person. You're still not sure how you know this, but fuck if you're not going to roll with it. You play with this, making silly expressions over breakfast, causing some anomalous relocations of plates and chairs, watching a water blob with 'ROBBIE MYERS PLACEHOLDER' scribbled on it eat breakfast transferring nutrients to you, and watching them ignore your very cool humanoid dragon pose-off antlers included as 'that's nice' material, but they take it in stride and/or forgotten confusion depending on the moment as you finish up and bike to school.
Ironically true to Lacey deciding to do something despite being explicitly told it doesn't work that way, with a bit of screwing around with water magic you are in fact invisible to the school. You leave your schoolbag on your...placeholder-blob-self, who locks your bike and shuffles off to class while you watch invisibly behind. You were apparently beneath attention in general to begin with, but as your first period teacher marks you as present you're pretty sure your increasing mental influence wave will hold. Surprisingly, Blob Robbie is better at schoolwork than you are and only barely bothers to look like you for visibility reasons, which is enough to get you to walk out of the room and browse the halls freely. You still receive Blob Robbie's sensory input and simplified decisionmaking process in the back of your mind, sort of like leaving a movie on in the background, but you don't feel any need for him to act any differently than expected. Yet.
So you're a water dragon, whatever anyone's expecting regular ol' human Robbie Myers to be doing is done, and right now nobody cares. You might or might not be able to use your being-beneath-attention to get revenge on Lacey, or decide the best revenge is living well, or just screw around under the protections of normality until you can really vanish from all this.