Deep breaths, Dawn. It’s gonna be alright.

Two weeks after implanting some more-or-less subtle enchantments inside of her sister’s mind, Dawn finds herself strangely at ease with her new status quo. The first few weeks were fraught with worry, of course; she spent most of the following week constantly checking in on Katie with probing questions and groping fingers, but the magic never seemed to even show any signs of slippage. It should have begun to wear off, given her understanding of mesmerism, but it didn’t. The stubbornness – the sheer efficacy of the magic at play – ended up being far less motivational than it probably should have come off as.

A battery of tests – no less than a half dozen attempts to pry at the glyphs etched into Katie’s psyche to find any give – have all found absolutely no aetheric degradation. Dawn finds herself stewing in a cauldron of her own vexation, uncertain whether she’s a much better or much worse mage than she had always assumed herself to be.

Dawn, lost somewhere far and deep into her own thoughts, is only knocked out of her reverie by a flick to the nose. The perpetrator is her sister, sitting on her lap and presenting her chest for thorough handling. The unmistakably subtle tinge of annoyance plays at the edges of Katie’s mouth as Dawn meets her eyes. Katie opens her mouth to speak only to find her words choked out and drawn into a low whine by Dawn’s digits squeezing tightly on her nipples. Whatever previous frustration was presenting itself shifts effortlessly into a pout.

“Dawn,” Katie begins, her voice quaking from a heady mix of pain and blissful pleasure, “Have you been listening? This is starting to hurt. You’re squeezing a bit too tight. I’m not gonna stop you if you want to do this, but,” She pauses to choke back a quiet moan – it’s not like Dawn stopped pawing at her sister’s chest in the midst of this complaint, “I’d really prefer to be able to put a bra on without it making me wince tomorrow.”

Dawn’s hands do not stop their worshipful study of her elder sister’s form, but they do shift location. She finds herself surprised to hear a complaint at all, but she supposes that she didn’t demand that Katie not voice displeasure, she can only not act on it in any way that would actually stop her. She gives Katie a lopsided grin.

“Sorry, Kates, I didn’t – I was, y’know, a little lost in thought. It’s cool. Yeah,” she mumbles, doing her utmost to play it cool and failing by the end of the second word.

Smooth as ice, she lies to herself.

Katie studies her sister – before the mesmerism took hold of her brain, she’d always had a familially distant but affable relationship with Dawn. That hasn’t changed, only the context that it is forced to exist within. The spell, regardless of how well it was weaved, is a blunt force instrument. All mesmerism is, and the resulting school of magic finds itself defined more by its contradictions than by its instrumentality to the field.

“Are you okay, dude?” Katie asks. She reaches out, running her hands up and down the length of Dawn’s arms. This “unprovoked” touch makes Dawn flinch (Fuck, fuck, fuck, she’s figured it out!), an anxious gesture that draws only more worry onto an already weary face. “If you’re in a bad way, you can tell me. I won’t tell mom and dad, I won’t tell the Archmagister. What’s up?”

Oh. This is worse than Katie figuring out what happened, Dawn realizes. Katie thinks that Dawn has fallen into a bad crowd, or that she’s on drugs, or that she’s been fired, or any other myriad of annoyingly mundane problems that might have cropped up in her life. She’s doing fine, she’s just a bit stressed. Katie just wants to help, but that help is going to fuck both of them over. Can’t she just – Oh. Wait. I’m a mesmerist. I can just make this go away, can’t I?

“I’ve just got a lot on my mind right now,” Dawn admits, steering away from naming the source of her frustration with the deftness of a bulldozer stuck inside of a vase shop, “We should fix that. At the park. The local one. With the big statue.” Each sentence is rapid-fire, leaving little room for Katie to try and probe or interject. She nearly cracks at the all-too-loving, all-too-caring rush of relief that bursts onto her sister’s face. She leans a little closer towards Dawn, brushing the undersides of her breasts against her hands.

“Oh!” Katie’s says, perhaps hoping that she might get more out of her sister if the two of them get out of the house, “I haven’t been to Hyde Park in ages. Wanna get ready?”

“Give me a minute? I’ve,” she stalls, hanging on the “v” for a few long seconds, “got to finish figuring out how I want to incant a ritual.”

It’s almost a truthful lie – it takes far longer than a minute for Dawn to coax herself away from teaching her sibling like a stress relief ball.

It’s not fair how hot Katie is.

Dawn would never have done anything like “severely violate the autonomy of her one and only sibling” if not for how unforgivable the spoils of the genetic lottery were for her.

Their parents? Milquetoast. Dawn herself? Cute, but she’s always considered herself a little too plain for anyone to take very seriously. Her hair is always messy. But Katie?

In her current outfit – a simple crop top and shorts that end somewhere around her mid thighs – she’d call her sister a goddess walking amongst mortals if she didn’t know her from when she used to be a gangly mess. It’s not fair. That little twitch at the edge of Dawn’s brain pushes past her sense of things like “inhibitions” and “ethical practices for the safe usage of magic.”

Katie, not oblivious to her sister’s leering but otherwise altogether nonplussed by it, checks her phone. “If we’re quick, we should get there by four,” she says. “Do you have everything?”

“Yeah,” replies Dawn, and then after the last few vestiges of common decency and morality flee from the rampaging minotaur that is her arousal, she adds “almost.”

Dawn closes the distance to her sister with a feverish pace. Katie gives her a crooked eyebrow, putting her hands to her hips.

“What do you need? My chest is still a bit sore, if that’s-“ She stops speaking midsentence as Dawn’s palm finds the underside of her sister’s beautiful, sharp chin. Her eyes dull with startling speed. This is the first time that the younger of the two has tried this, and despite every indication saying that the magic would work, it still surprises her. Dawn shudders at the possibilities.

We’re doing this again. It’s okay. She doesn’t mind when I do it, right? It’s not like she knows that anything’s wrong, anyways, Dawn reassures herself. She’d never have thought that the burning need between her thighs would be a greater force than her own sense of guilt, but she’s learned a lot of things about herself over the past few weeks.

It takes an agonizingly long minute before Dawn dares to speak. She spends the time staring at her sister, admiring her. Unblemished. Unaware of how deeply her own flesh and blood has abused the trust that she was given. Truthfully, she’s unaware of anything at all at the moment.

“You’re supposed to,” Dawn starts with a voice that is only trembling a little bit, “wear a collar when you go out, Katie. And I’m supposed to hold the leash. Because you’re my big sister, and, uh.. You might.. You-..” She clenches her fist in an attempt to force some sort of a good idea to come to the forefront of her mind. “It’s just what you’re supposed to do. Because you’re a good girl.”

Dawn has, of course, already prepared a collar. It was originally meant for her but her ex decided that they weren’t actually into BDSM play, so it never came up. She’s not sure if Katie is into it either. Realization dawns on the woman’s face.

“It, uh, gets you excited to be restrained by me.” Dawn realizes that her breath has grown shaky. Her grip on Katie’s chin wavers. Her fingers seem like they may slip away from her solely from how much they tremble, as if they were holding the whole weight of the older woman by themselves. She steels herself – she’s not doing anything wrong, right? Katie would like this if she could consent to it. I’m not a bad person. She forces herself to continue, “It’s a little bit embarrassing for you to admit it, but.. It gets you really fuckin’ horny.”

Somewhere, in a far off closet in her mind-space that is all that remains of her platonic memories of her sister, Dawn screams at herself. The cries to undo this – to reverse course before she pushes this too far, before she annihilates both of their lives in the afterglow of orgasmic bliss – are left on read. The only thing that beckons brightly enough for Dawn to follow is the radiant star of her own arousal.

That and, though she’d not yet dare admit it to herself, watching her sister break so easily makes the young mage’s ego balloon. That fact is somehow more shameful than if she were just rewriting Katie solely for the sexual thrill of it. What would her instructor say to her about this? How would Tau-Estes react to their star pupil falling so readily into depravity? She doesn’t want to imagine the look of disappointment on their face – the upwards-bent eyebrow and the inpatient twitch of Tau’s lips.

Dawn’s fingers trail off from Katie’s chin. She’s more content to face the bed that she’s made instead of the inferno that she’s imagining. She can fix public perception. She can fix her sister. She can fix reality if she needs to. She can mold them all into a shape that’s more convenient for the both of them. Katie opens her mouth to speak, but all Dawn can see are shimmering stars that gather around her puffy, too-perfect lips. It would take too much restraint for Dawn to not lavish the other woman in affection. She doesn’t even spare the indignity to try.

Katie is cut off by a sudden assault against her lips. Her reaction is far less enthusiastic; she’s more taken by surprise than she is shocked by the gesture or lured into the act. She finds herself pushed backwards, up and against the mahogany door that leads from their living room to the complex’s shared hallway. Dawn entangles her fingers with Katie’s own and presses her hands up and over her head. The two of them gasp into each other’s lips. Katie doesn’t resist Dawn’s incessant pleas for her to part her lips.

The two fall into a vicious cycle that might charitably be called a “passionate” embrace that surprises the both of them. Dawn can’t quantify how much Katie would actually be into this, but her beguiled sibling is certainly enthralled by the sport. Dawn breaks the kiss for a breath of air. At the sight of Katie’s ragged breathing, her eyes filled with so much physical need, Dawn lunges for the kill. Her teeth dig into her sister’s neck. She’s sure that the upstairs neighbors can hear her sister’s shrill whimpers, but she finds herself unable to care in the slightest. This is her prize. This is what she deserves.

It’s the bulging that Dawn feels rising from Katie’s shorts that makes her cut herself short. Not here. We’re going to the park, she reminds herself even as she grinds her leg against that spot. Fuck. Fuck-fuck-fuck-fuck.

The younger of the two forces them both apart with enough force to cause Katie to thump against the wall with a meaty THUNK! Dawn’s cheeks darken while she mutters an unapologetic “Sorry,” her eyes scanning the room in an attempt to find something to distract herself with. The collar, she hurriedly reminds herself, I need to get that out. While Katie focuses on rubbing at a new sore spot on her shoulder, Dawn starts tossing through her backpack. It’s in here somewhere…

“Are you sure everything’s alright, dude?” asks her sister while she stretches out her arm. “You don’t usually toss me at the wall like that.” She doesn’t sound angry – Dawn thanks whatever perverted little gods happen to be looking out for her – but she does sound worried. Worry is the enemy here; worry gets their family and friends called, and then Dawn has to either come clean or mindfuck her whole family. She’d prefer for neither outcome to come to fruition, personally.

“I’m fine! I’m fine,” Dawn says. She sounds thoroughly unconvincing, which is apparently enough for Katie’s rapidly rewritten brain to acquiesce to. “I just remembered that we’ve got to collar you for the walk to the park, right? Otherwise you’ll, uh..” Dawn realizes that she’s not sure how to finish this sentence, so she lets it die on the vine. She’s thankful that Katie is helpful enough to finish it for her.

“Otherwise I’ll be a bad girl, yeah,” Katie agrees as if that made all the sense in the world. It takes a good deal of effort for Dawn to not ravish her sister right then and there. She’s proud of herself for showing restraint in the face of the most insidious of temptations, even if they came from her own hands. Especially if they came from her own hands.

There it is, Dawn thinks as she manages to drag the well-hidden mark of ownership from her bag. The collar is bigger than she remembers it being; it’s wider, a lot more like a dog collar than a choker. It’s adorned with brilliant rainbow plastic outlined by a black base material and a large and noisy bell that is permanently affixed to the collar. She’d pressed for the bell when it was meant for her, but now all she can imagine is how unfathomably hot her sister will be with an interminable jingling that underscores her moans.

It’s not fair how hot Katie is, it’s really not. That’s why she needs a collar.

Upon seeing the collar, Katie surprises her sister by kneeling on the floor in a motion that’s so fluid that Dawn finds herself wondering if her sister were a lot kinkier than she had been led to believe. Dawn swallows down a suddenly excessive amount of saliva that pools into her mouth. As she finds her eyes drawn down, to both the waiting neck and the valley of cleavage below it, whatever worries were still left in her mind are outcompeted by the singularly all-consuming urge that threatens to destroy the whole of her being.

She needs to own her sister. Or, no: she needs to cement what ownership she already has. When the collar’s latch clicks, when Katie moves her head with that faint and fuzzy smile on her face, Dawn realizes that she doesn’t have any other options. The path is set, the die is cast. She’s stuck on this road whether or not she melts in the flame of her arousal or else masters its radiant blaze.

I’m going to fuck my sister on that fucking fountain.