Harry did like it up here. He'd never been in the ritual room before — Grimmauld was huge, with dozens more rooms than any town-house should be capable of containing (magic, he assumed), and Missus Weasley's obsessive cleaning campaign hadn't reached the back rooms on the third floor. Unlike the rest of the house, it was positively Spartan. It was relatively large, about five metres by five, and completely undecorated. There were no windows, and the walls and floor and even the ceiling were tiled with black stone that seemed to drink in the light from his wand. The tiles weren't regular squares, either, but a swirling mosaic of different shapes. As soon as Mimi closed the door behind them, pinpricks of cold, blue-white light appeared at every intersection between them, like being surrounded by an entire galaxy of stars.

She smirked, leading him to sit on the floor in the middle of the room. "That's exactly what it is, you know. The galaxy. This is what the sky would look like if we were just floating in space, without the Earth getting in the way." Put out your wandlight, you don't need it, she whispered directly into his mind, which was still really weird, but he was getting used to it. (She might be onto something with that whole you're a legilimens, too thing, because it didn't feel nearly as weird as he sort of thought it should, having her think at him like that...)

He did. It took a few seconds for his eyes to adjust, and a few more seconds for his brain to stop fighting to recognise the pinpricks of light as patterns on a wall, when he couldn't even tell where the walls were. Without even the wand-light to anchor him to some sense of reality, it was a little disorienting, but undeniably beautiful. It felt at once as though he was in a vast, open space, and a very small one, his sense of perspective gone entirely wonky, but it felt...safe, enclosing them — the outside world might as well not exist anymore, there wasn't so much as a visible crack beneath the door — without making him feel like he was trapped.

Mira's smirk faded into a much softer, sadder smile. "It's even better when the Family Magic is awake. There's an anti-gravity ward so you can actually float while you meditate, and the magic is strong enough it feels like you're just dissolving into the universe. It's my favourite place in the world."

Harry...didn't really know what to say to that. He didn't really know anything about the Black Family Magic. He didn't even think Sirius had ever mentioned it to him. But he didn't want to think about Sirius. (Which was made difficult by the fact that Mira really looked a lot like him, he kept thinking of him every time he saw her.) After a few seconds, he cleared his throat. "So, um. What do we have to do, exactly? For this whole...soul magic thing, I mean."

"You don't need to do anything," she said, cracking open the book she'd brought up with her, even though there was barely enough light to see each-other's faces, much less read.

What are you talking about? There's plenty of light... she 'said', amused. His perspective suddenly shifted so he was looking at himself, presumably as she saw him at the moment — much more clearly than he could see her. Well, not quite. You can't see magic. Hang on... A moment later, the vision changed, a sort of light radiating from every surface in the room, swirling around and through him, but without actually illuminating anything. And then it was gone, and he was looking at her as she returned her attention to the book.

"That's why I don't really like fully inhabiting the people around me like Thom does." It was incredibly weird and not a little uncomfortable to hear her talk about Voldemort like he was just another person she happened to know. Harry was sort of trying to think of the version of him she mentioned all the time as a completely different person, actually, which was easier than he'd expected it to be when he first decided he was going to have to, because the "Thom" she talked about seemed very different from Voldemort, or even the diary horcrux version of himself. "Yes, other people's emotions tend to be more vivid and immediate than my own, but their physical and magical senses tend not to be as good. Alright, let's try this one first..."

She murmured a few long, fluid phrases under her breath, too quietly for him to pick out the actual words, or anything other than that he didn't recognise the language.

Nothing happened.

She didn't seem annoyed though, like he always kind of was when he couldn't get a spell to work. A few seconds later, she cast another one, different, he thought, though he wasn't sure.

This time, a silver web or lattice of light flickered briefly against his skin, shockingly bright in the darkness of the ritual room.

A third spell, this one much longer than the other(s?) produced a shimmering green-gold cloud, sort of containing a complex ball of silver lace, with an ugly, pulsing, red-and-black chancre on one side, ragged and...almost torn-looking around the edges, like it had gotten caught in the ball and had been damaged trying to escape. Or... Were there two layers to the ball? Looking more closely at the shifting patterns of light, it seemed like there might be, with the repulsive, red-black thing sort of trapped between them. It was moving, too, but always within that same orbit, unable to reach out into the green.

That made Harry feel a little better, that whatever this thing was, it couldn't...get to him, but only a little, because the green kept swirling through the lace and touching it, and he might've been imagining it, but it almost seemed like it came away a little darker and less golden every time it did.

He knew instinctively that that was the problem — not that the thing, the whatever it was giving him some insight into Voldemort's mind (that wasn't actually like...part of him somehow, was it?) — was trapped, but that it was there at all. It was disgusting, just looking at it sent cold shivers down his spine. He wanted it gone!

"Hmmm...I thought so," Mira said, with a sort of grim satisfaction which, oddly, reminded Harry of Dumbledore, as he'd looked through a haze of green smoke, the twin serpents produced by the mysterious silver instrument he still didn't know the name or purpose of dissolving as Harry and Ron waited anxiously for any word of Mister Weasley. (It had only been a year and a half ago, but it somehow seemed so much longer than that...) "Yeah, I don't know what that was, he makes — made — those things himself," she added. "But this," she gestured at the glowing image between them, "is a model of your soul. You're the green. Voldemort's the black. The silver is a spell I assume Lily did. I think, based on what it's actually doing and what I picked up from Sev about Samhain of Eighty-One, it was meant to contain another soul, probably hers, to protect you from a soul-magic attack, forming it into a shield around your soul.

"I don't know exactly how she did it, or why that piece of Voldemort's soul is trapped in it instead of hers, but the good news is, you've been exploiting the sympathetic resonance between this part of his soul and the part that's out there being a fucking idiot to scry his mind at a distance, not actually legilimising him directly. Which would be why he hasn't noticed you, this thing just acts as a sort of simultaneic antenna, resonating in tandem with his mind, but no longer sufficiently connected to the whole to permit direct possession." Obviously recognising that he had no idea what any of that meant, she added, "It's sort of like a horcrux, insofar as it's still metaphysically bound to him, but distantly enough that you can't use it as a conduit to possess him directly or vice versa."

"What? How is that good news?! I don't care if it's not actually connected to him, I don't want a bloody Voldemort antenna or a fucking horcrux in my head! How do we— You do know how to break it, right? Please tell me you know how to break it..."

"Well, no, actually, like I said, I have no idea what she actually did. It's possible it's not actually a formal spell, but the product of a ritual she invented for this exact purpose. In fact, that's probably more likely, honestly, that would explain why it's anchored to that sowilo carved into your forehead. But the problem's not actually the spell-net, it's clearly a one-way containment that doesn't affect your ability to reach into and through it. Which means we don't really need to break the spell to reach and destroy the trapped soul-fragment."

Harry, who had been on the verge of panic as she explained that no, she didn't know how to break the spell, was struck by a sense of relief so sudden and strong, if he hadn't already been sitting down, he might have fallen to his knees. "Yes! Good! How?"

"Er..." She actually hesitated, which was just weird. "I would ask you not to flip out when I explain, but I'm not sure you can. Just...please don't tell Ron, Hermione, or Ari– Tonks. And keep reminding yourself that you don't care how I get rid of it, as long as I do."

"What? Yes, fine, whatever. How do we get rid of it?" he repeated, somewhat more confusedly, now, but no less urgently.

"Ah...I'm going to need to possess you and extend my magic through you to subsume the soul-fragment. You don't actually need to do anything except try not to fight me — I will have to distinguish myself from you to force the fragment to resonate with me and pull it through you, rather than just letting it out of the net into your mind — but it might be...sort of disturbing to observe."

Harry...wasn't entirely sure what that meant, or why he would be freaking out about it.

Instead of explaining she sort of...pushed a memory at him. It wasn't exactly like dreaming of being Voldemort, but close enough to make him uncomfortable, even before he realised that he was watching the scene play out from the mind of twelve-year-old Mimi, or exactly what she was doing. It was dark — her eyes were closed — but she could feel the enchantments on the walls and furniture around herself, and the man lounging in an armchair off to her left, and the rabbit sitting in her lap.

Good.

The thought was slipped directly into her mind. Mimi still wasn't used to that. Sev always told her not to think at him, that it was rude, and refused to do it back. That Thom did, actively encouraging her to "talk" to him telepathically, was probably the thing she liked best about him. It was definitely the thing that made her feel most at home with him. It almost made her want to cry, that she'd decided to stay at Hogwarts the last five years, when she could have been here, with her grandfather, who actually understood her.

(Grandfather?! Harry recoiled. What the—)

Sev was great, and she loved Bella, and Helena had been the best mum she could've asked for—

(Maybe she meant "grandfather" like that, he thought, though he wasn't entirely convinced. It hadn't felt like she meant it like that. But Voldemort couldn't actually be her grandfather! That was just impossible!)

—and she was sure she'd learned all sorts of things from the other ghosts that she never would've learned anywhere else, she didn't actually regret staying, but she'd only been here for two weeks, and she'd never been this comfortable before. Sometimes it was a little overwhelming, being around humansall the time, but no one got angry with her for not always being able to hold herself back and sometimes getting into their minds — the ones who didn't want her to just used occlumency to push her back out, gently, like Sev — and Thom was teaching her all sorts of things Sev never had, like how to possess animals and do compulsions and—

Focus, Mimi, he thought at her, a little amused and a little exasperated. He did find it a little frustrating teaching someone as distractible as her, but he had taught Bella when she was a kid, younger than Mimi, even, so she figured he was sort of used to it. On the rabbit, he reminded her.

Yes, right, the rabbit. It was a soft, placid thing, much larger and stronger than she'd expected, almost as big as some of the cats at Hogwarts. And it was cute, with its big ears and twitchy little nose. She knew it was a food animal, but still. Adorable. It liked being petted (she still couldn't get over how soft it was), but it had hopped away when she'd tried to pick it up and move it into her lap, which was annoying, because she just wanted to hold it close and snuggle it. That was, she suspected, part of the reason Thom had decided that they'd start practising direct subsumption with rabbits. That feeling of wanting to hold it, to wrap herself around it and luxuriate in the warmth and softness of it, was only a small step away from the desire, the hunger he felt to take other people's feelings and energy into himself and make them his own.

Yes. So we reach out— He did, using Mimi's magic to do it, like standing behind her and guiding her hand, almost (metaphorically). —and we surround the target— In this case, the rabbit's entire life-spark.

What passed for a mind in most animals was tiny, incredibly easy to dominate. Compelling conscious beings was easy, but with animals, she didn't even have to try, she just had to want them to do something in their general vicinity and they would. (As soon as she'd decided she wanted the rabbit to want to sit in her lap, rather than just physically moving it, it had crept right back, its instinctive wariness of her crushed.) Possessing them entirely was a little harder, but only because she kept getting distracted by falling into experiencing the world through their senses — in this case, by how nice it felt to scratch her rabbit-self behind the ears with her human fingers.

But her mind was so much larger than the rabbit's that flooding its entire mind with her magic and taking over its body was a piece of cake. She didn't even have to try to make herself feel like she belonged there, because A, it wasn't conscious and therefore couldn't fight back, and B, she didn't need to get inside it, she could just surround the whole thing.

—and now, rather than finding the frequency of the Other, we bear down, forcing its energy to resonate with us, like a compulsion encompassing the entirety of the target.

That part was almost impossible to describe, the way it felt to impress her will on another mind. It did feel sort of like casting magic, except on another mind rather than external magic...but she couldn't describe that, either, except that it felt kind of like compelling someone, but impressing her will on external magic rather than another mind.

It wasn't difficult, anyway. In fact, it might be the second-most-natural thing in the world, after getting into another mind in the first place. She just...wanted it to feel like hers, pushing a little pulse of energy into it to change it, and it did.

Good. And then we withdraw, bringing the newly attuned energy with us.

Withdrawing didn't really have much meaning when there wasn't really an Other anymore, but she did pull back a little closer to her body, bringing the rabbit's mind-magic-life energy with her, pulling it deeper into herself. Its heart stopped beating as its magic lost contact with its body, and she felt it, which startled her enough she sort of dropped her hold over its stolen life, letting it revert to feeling Other-y again, but it was already trapped inside of her aura, completely cut off from the outside world, so it was probably fine.

Yes, Thom confirmed, amused. Now for the relatively tricky part, you need to assimilate the energy into your own being, not just forcing it to resonate with you, but stripping it of its Otherness entirely. When you've practised a bit, you'll be able to strip the Otherness away without destroying the memories and patterns that the magic you've captured holds— Instincts, mostly, in the case of the rabbit. —but for now, we'll just render it down into raw energy, retaining no patterns from its former existential structure.

Like ambient magic?

Essentially, though far more dense. The energy of a living thing is far more concentrated than that of non-living things, and that of a conscious being even more so. You certainly can just reach out and absorb ambient magic, assimilating it into your self, but unless you somehow concentrate it first, you'll hardly notice. The illustration that accompanied the thought was contrasting sunlight falling naturally against sunlight focused with a magnifying lens to set a scrap of paper alight.

...Okay, she'd have to come back to that idea later. (Thom found it amusing how intriguing she found the idea of just assimilating ambient magic directly, though he didn't say why.) Now, though...if the idea was she just needed to...destroy the existing patterns in the foreign magic...

She sort of reached out to it and combed her own magic through it, like working a tangle out of a curtain-tassel with her fingers, or a plait out of her hair. It took a few passes at different 'angles', but any structure the magic had held quickly fell apart, smoothing out into something more...fluid than it had been. She kept running her mental fingers through it because it felt nice, like dragging her physical fingers through water, though she had to ask, Am I doing this right? because he'd said this was the tricky part, and it seemed too easy...

Thom chuckled. Actually, out loud chuckled. Yes. I said it was relatively tricky, compared to overwhelming another mind — which, from a technical perspective, it is. Not that it would actually be difficult. I would have been surprised if it were, actually, given that you seem to have inherited my predilection toward the domination and subsumption side of legilimency.

(Inherited?! Mira! What does he mean, inherited?! Harry thought, as pointedly as he could.)

(He must have gotten his point across, because a moment later, she thought back, Magical talents are heritable traits. He's our biological grandfather. It's not surprising that we come at legilimency from the same perspective...)

(He's our what?! How?! This time she ignored him. The memory continued playing out, though honestly, Harry was a little too busy flipping out over I'm not related to that– that monster! I'm not! to pay attention.)

Oh. So how do I do the assimilating part?

...Actually pay attention to what you're doing for a moment.

What? He let her feel his exasperation as he turned her attention to the magic she was still playing with. It didn't really feel like she was doing anything, but she must have been, because there seemed to be less of it now.

...Look closer...

She did, focusing a little more on exactly what she was doing, the way the foreign magic sort of...seeped into her 'fingers', melting away like sugar on her tongue. The same thing was happening at the edges of it, where it was just in contact with the rest of her mind, sort of dissolving away. Dissolving into her, making her feel, now that she was paying attention, a little more...energised. A little giddy — giggly, and like she needed to move, go do something physical to burn it off, sort of like the (very) rare occasions she'd been allowed to have real coffee. And a little just...more, like she'd somehow managed to grow half an inch taller overnight, and now there was just more of her. Except magically.

That was so neat!

There it is, Thom thought, a little smugly, but mostly amused. Congratulations, Granddaughter. (NO.) You're officially an evil metaphage who should be killed on sight as a practitioner of the most dangerous and terrifying of all the anathema Dark Arts.

Wait, what? Seriously? That's all metaphagy is? Somehow, she hadn't realised that "direct subsumption" was the same thing as metaphagy. Books always talked about metaphagy like it was super scary and dangerous and capital-E Evil, but they never said what it actually was. That was what anathema meant, magic that was so dangerous the Light thought people shouldn't even be allowed to know anything about it, much less how to do it. She wasn't certain if she was more outraged or disgusted that Dumbledore and Uncle Jamie would want her dead just for eating the magic and life force of a bloody rabbit, but either way, that was ridiculous!

Oh, no, that's certainly not all metaphagy is. It is, however, more than enough metaphagy for today. Take the carcass down to the kitchens and go annoy Bella, I'm sure she'll be delighted to see you even more hyperactive than usual.

She giggled, opening her eyes and bouncing to her feet to give him a hug first. Thom thought hugs were weird, but Mimi was pretty sure that was just him. Uncle James thought she ought to have hugged him when he left after his visits to the school. Embracing one's family was simply what one did when offering greetings and farewells (NO! Stop thinking of him as your family! Harry railed, to no avail.) and it was rude and hurtful that she wouldn't, because it was like refusing to acknowledge that they were family, which was exactly what she was doing. But she actually liked Thom, and he didn't dislike hugs, he just thought she was being a bit silly and childish and that the idea of having family was itself sort of weird (Stop it!), so as far as she was concerned, hugging him was perfectly acceptable behaviour. "Thank you, Thom!"

Mimi wasn't sure whether she was supposed to hear him think, You're such a strange child... It was easier to legilimise someone when she was touching them, which she hadn't realised until Henry and his friends started visiting her, because she was just never around humans, so it was possible that she hadn't been meant to catch it. Either way, all he said aloud was, "You're welcome, of course." Though he caught her wrist when she turned to skip away to add, "Mira. I won't tell you not to practise subsuming energy on your own, but you're to bring any animals you kill to the kitchens so they won't physically go to waste, and do bear in mind that if you subsume too much foreign energy too quickly, you can and will make yourself very ill. Don't try subsuming feelings or knowledge from a conscious mind until I tell you you're ready. And all joking aside, you should be prepared for other people — anyone other than Bella, even other legilimens — to find it somewhat disturbing if you tell them that you're practising metaphagy. Or direct subsumption — other people here are aware of the meaning of that term, in the context of legilimency."

"So, don't tell Sev?"

Thom shrugged. "You can tell him if you like, but if you do, be prepared for him to disapprove. I'm sure he won't hurt you or actively attempt to stop you, but he'll almost certainly try to convince you that you should." He smirked. "Eating people is an even worse habit to get into than telepathy."

She pouted at him. "Fine. I'll think about it. Can I go, now?"

"Yes." He let go of her wrist. She got about two skips away before he said, "Mimi," again.

"What, Thom?" she huffed, annoyed.

He pointed at the rabbit, lying forgotten and cold on the floor. If you make a habit of leaving dead animals lying around my house to rot, I will absolutely make you forget I ever taught you this particular skill.

"Oh, right. Sorry..."

Harry blinked, and he was in the star-filled ritual room again, with Mira sitting on the floor, half cross-legged, her other knee pulled up to lean forward against, watching him intently. "What the hell do you mean, he's our grandfather?!" he demanded immediately, scrambling to get away from her, his hand finding its way to his wand of its own accord.

"That's what you're choosing to focus on, here? Seriously? I tell you that I'm planning on using anathema magic to subsume a fragment of a human soul out of your mind, and you honestly think the thing you should find horrifying is that you're related to Thom?"

"I'm not!" he protested.

"Lily was adopted by her muggle aunt when she was a baby," the girl explained, calmly unconcerned that he was holding her at wandpoint, on the verge of stunning her so she'd just stop saying that. "Sort of like you were given to Petunia, except Petunia's actually your mother's cousin, not her sister, and no one told Lily she was adopted until Hecate mentioned that Thom was her father in the middle of a ritual — long story. I don't know if that ritual happened in this timeline, it might not have. It was right around the time we split. Actually... It might be the turning, point, honestly. I don't remember exactly what they were doing, Annie told me about it when I was about four, but I think it was something to help Thom, so it very easily could've been Lily breaking the tynged that drove him insane in this universe, if that happened in my timeline, too...

"Anyway, the point of divergence was well after Lily was born, so if Thom was her sire in my timeline, he was in yours, too."

He didn't want to believe it. He wouldn't!

...But he couldn't help remembering all those years ago, down in the Chamber of Secrets, the horcrux— I wondered, you see... There are strange likenesses between us, after all... We even look somewhat like...

Mira grinned. "If it helps, the Blacks have a saying: You can't choose your family, but you can kill off the ones you don't like. Which is honestly probably why the House completely died out in this timeline, most of them never did like each other. Without the Dark ensuring they'd survive as a House, it's not really surprising they didn't.

"Speaking of, I need to get back up to Hogwarts today, so. Do I need to make you sit down and let me get that piece of Thom out of you, or are you going to do so of your own free will?"

He sat down, a little farther away from her than before, still wary and defensive, but what was it she'd said? Keep reminding yourself that you don't care how I get rid of it, as long as I do? Well, she was right about that, at least...