Triquetra

"Exactly what is that thing?" Ron asked dubiously, looking at the parchment Hermione had spread out on the table in front of them.

Hermione huffed. "It's a triquetra, Ron," she said. "A triquetra is a figure formed from three circular arcs of equal radius, producing three overlapping vesicae piscis."

"Speak English, Hermione," said Ron, tracing the symbol on the parchment with his finger. "I haven't got a clue as to what you said just now."

"You put a bunch of semicircles together to get this shape, then," Hermione snapped. "And if you'd paid any attention in History of Magic instead of playing hangman with Harry, you'd know that it is an ancient symbol that's often used to represent people or concepts in groups of three."

"You try to get through a History of Magic class without playing hangman and see how long you stay awake," Ron grumbled. He looked over at Harry, to gauge his opinion, but Harry was busy rifling through one of Hermione's folders. "Anyway, what do you think it'll do?"

"Well," said Hermione. "With some modifications, I believe we'll be able to use this as a sort of warning device, to send out an alert if one of us is in some sort of danger or trouble." She snatched her folder out from under Harry's nose and flipped through it, fanning parchments out on the table beside the diagram. "It should also serve as a sort of homing device. If one of us is separated from the other - say, the way Harry was taken away to that graveyard after the Third Task - we'd be able to locate the missing person and Apparate there immediately."

"That's kind of how the Dark Mark works," said Harry quietly, after a pause.

"Yes, I suppose that's true," said Hermione.

"What, you're going to mark it on us?" Ron yelped.

"No one can take it away that way," said Hermione. "And we can't lose it, either."

Ron considered this for a moment. "I reckon that's all right then," he said, picking up the diagram again and studying it carefully.

Harry peeked around Ron's shoulder to study the diagram, then looked up at Hermione. "When can we do this?"

Hermione looked flabbergasted for a moment, and then said, "I suppose - I mean, I've everything we need already. And it's not like we have to wait for a full moon or a particular alignment of celestial bodies, so I suppose we could do it whenever you like."

"Right now," said Harry, and the determined look in his eyes was enough to give Ron a little chill up his spine.

Since it was Christmas break and there was no Yule Ball - that being an activity connected with the Triwizard Tournament - nearly everyone had gone home to be with their families. The seventh year Gryffindor boys' dormitory was deserted except for Harry and Ron, and they were sitting on the side of Ron's bed in their pyjamas when Hermione sneaked in late that night. She was in her pyjamas too, but was loaded down with books and her schoolbag.

"What's all this?" Ron asked, as Hermione emptied the contents of her bag onto Ron's bed. There were several sheets of parchment covered in Hermione's neat handwriting, a bottle of ink that seemed a lot thicker than regular ink, three brand new quills, and a bottle of what looked like a rather sludgy potion.

"Did you think we'd just be able to swish and flick and have it magically appear?" Hermione said as she continued unloading her bag.

"Yes," said Harry and Ron together.

"Unfortunately, it takes quite a bit more work than that." She swiped the glass from beside the pitcher of water on Harry's bedside table, scowled at it a moment as if to analyse its cleanliness, and then used a Scouring Charm on it. Then she uncorked the bottle of potion and poured out a dose, handing it to Harry. "Here."

"What's this for?" Harry asked, peering at the potion.

"The marking is going to hurt," Hermione said. "Just drink it."

Harry downed the potion in three gulps, pulled a face, and handed the glass back to Hermione. "Disgusting."

"Good." She poured out another dose and gave it to Ron.

Ron stared at the potion. It looked... fuzzy. Like something was growing on it. And it smelled funny too. But Hermione had her hands on her hips and was giving him a Stare, so he gulped it down and tried not to puke it back up when he gave the glass back to her. She poured a final dose of potion for herself, wrinkling her nose when she drank it.

Then Hermione selected three of the parchments from her schoolbag, each with a triquetra neatly drawn on it. "Hold out your arm," she said to Harry, uncorking the bottle of ink and selecting one of the three new quills. Harry looked at Hermione's quill suspiciously for a moment.

"It's just a regular quill, Harry," said Hermione, holding it out for him to see. "I have to trace the pattern onto your skin first, and I wanted to use a clean quill."

Apparently satisfied that it was nothing like Umbridge's quill, Harry pushed up his sleeve and held out is right arm, wrist up, and Hermione laid the parchment across it. She motioned for Ron to hold the parchment still while she traced the design from the parchment onto Harry's skin with the unusually thick ink and the brand new quill, then lifted the paper carefully and blew on the design to dry it.

"That didn't hurt," said Harry with a frown. He flexed his arm experimentally, staring at the design standing out on his pale skin.

"We're not done yet," said Hermione briskly. She took out another piece of parchment and a fresh quill and repeated the process on Ron's arm; then Ron held the paper steady while Harry traced the design on Hermione's arm.

"Now what?" asked Ron. This part of the process had been easy, and he didn't know if that was a good or a bad thing.

"That just outlines the design," said Hermione. "Now we have to actually turn it into a mark, sealing it with magic." She pulled her wand from her schoolbag. "We'll need our wands for this..."

After Harry and Ron had retrieved their wands from their bedside tables, Hermione explained the incantation and had them practise it a few times. It felt funny in Ron's mouth - it sounded like Latin, which they were used to using for their incantations, but somehow it was a little off. Hermione made them say it over and over until she was satisfied that they'd done it correctly; to Ron it seemed like quite a long time. Then she asked Harry to hold out his arm again.

"Since you're the one most likely to need this," she said softly, biting her lower lip, "let's do you first."

Harry nodded, flexing his fingers, and Hermione wrapped one small hand around his wrist. As bony as Harry was, even Hermione's slender fingers went around his wrist easily, holding it in place.

"You mustn't jerk your arm away, even though it's going to hurt," she said, taking up her wand with her other hand. "We have to outline the mark with a continuous stroke to seal the magic in the mark completely. And Ron, I'll need you to say the incantation with me, and help me guide my wand along the outline I drew here, so that both of us will be able to seal our magic into Harry's mark. Then you and Harry will need to do the same for me, and so on." She said this all very calmly, as though it was perfectly normal for them to be drawing strange shapes on one another's bodies like this.

"All right," Ron said, wrapping his fingers over hers on the handle of her wand. It was then that he noticed that her hand was shaking, just the tiniest bit - perhaps she wasn't quite as calm as she looked - and he squeezed her fingers.

Harry would not look at either of them, but kept his eyes fixed on the neat black outline on his forearm.

As Ron and Hermione spoke the incantation, they pressed the tip of Hermione's wand to the edge of the triquetra drawn on Harry's skin, and the ink began to hiss and bubble and smell like burnt feathers. Harry clenched his hand into a tight fist, biting his lip and making a choked noise in the back of his throat, and Ron's free hand went to Harry's elbow, gripping it and steadying him.

"Almost done," Ron muttered, concentrating on tracing the outline on Harry's skin along with Hermione. It was hard to guide the wand tip along the outline without lifting up, and knowing that it hurt didn't make it any easier. Harry began to shake from the effort of holding still, and Ron gripped his elbow tighter until they were done.

When Hermione pulled her wand back Harry stared down at the angry red mark on his arm, touching it tentatively. "Not... too bad," he said, wincing.

"Right," said Ron. "Not bad at all." He couldn't believe that Harry wouldn't admit that it hurt; but then again he could believe it. Harry was used to things hurting, after all. He pushed his sleeve higher up over his elbow and said, "Me next, then?"

Ron yelped when they pressed Harry's wand tip against his skin. "Fuck!" he yelped, and would have yanked his arm away if it weren't for Harry's grip on his wrist. It hurt, it really hurt; the ink bubbled and hissed just as it had done on Harry's arm, and it felt as though a tiny stream of boiling oil was running along his skin. The worst thing was that he couldn't pull away from it. He had to... wait. As they completed the outline, closing the stroke, it seemed as if a surge of... something... flowed from the tip of Harry's wand and around the outline, tingling and burning along the inked mark. Magic? The pain made it hard to think.

After a minute to catch his breath, he took out his wand, and he and Harry guided it along the mark on Hermione's arm. He didn't want to; he knew how much it fucking hurt, and didn't want to inflict that on Hermione, but she held her arm steady and didn't pull away. She couldn't stop the tears from rolling down her cheeks though, nor could she stop the whimper as they sealed up the figure and pulled the wand away.

Ron suddenly felt light-headed and shaky. His knees crumpled and he sat down heavily on the edge of the bed. His arm burned and throbbed and everything smelled burnt and acrid, making his stomach churn.

"I don't feel so well, now," said Hermione quietly, and she lay down on the bed, curling up against Ron's pillow and closing her eyes. Ron scooted up to lay beside her, rubbing her shoulder.

Harry was still standing beside the bed, looking a bit green. Ron wasn't sure whether Harry was going to throw up or pass out, so he patted the space on the bed beside him, motioning for Harry to come over. Harry considered it for a moment and then sat down carefully, stretching out beside Ron but not quite close enough to touch him.

"Did it work?" Harry asked. He was so close to Ron that his breath tickled the back of Ron's neck.

"I don't know," Hermione whispered. She turned over, holding her arm close to her. Her eyes were red and puffy. "I think it did, but I can't tell."

Ron looked down at his arm, where the triquetra's outline was still angry, throbbing red. And a second later he felt - and then saw - Harry's fingers slide down his arm to brush hesitantly over the mark.

Ron moaned.

It hurt - the skin there was still sore and burning - but it was extremely sensitive, and the sensation of Harry's touch was cool and wonderful. It made him shiver, and he arched his back a little. Harry had moved closer, and when Ron leant into him, he felt Harry's body behind his. And Harry was shivering too.

"Ron, are you all right?" Hermione asked, looking concerned.

Ron whimpered when her fingers joined Harry's on his arm, and he shook his head. "...dunno..." he whispered. "Feels... weird."

"Weird?"

It was the strangest sensation he'd ever felt, and he couldn't describe it, so he slid his fingers along her wrist, touching gently at the edges of the triquetra on her forearm. "Like this," he whispered, tracing the brand they'd put there.

"Oh..." Hermione breathed, her eyes falling shut. "It's like I can feel you..."

That was exactly it, Ron realised. He could feel them - not only Harry's body aligned with his behind him, and Hermione's softness curled against him in front, but he could feel what they felt. He felt what they felt as they touched him, how they felt what he felt, a constant feedback loop of sensation that he could barely comprehend. Hermione's fingers moved up his arm to brush against Harry's mark, and Ron could feel the sensation that Harry felt - and feel how Hermione felt it as well. It was like swimming in feeling, and Ron wasn't altogether sure he wouldn't drown.

It was so eerie and unexpected and incredibly intimate. They were barely touching each other, but the intensity of the sensation in each touch was more than any of them anticipated, and it wasn't long before hands moved from the marks to other areas, fuelled by the intimacy of their connection. Fingers slipped under shirts, tracing over soft, warm skin; lips moved languidly over throats and jaws and shoulders; and tongues slipped over tongues, exploring and tasting and sharing. It was so overwhelming, this continuous loop of feeling, that when Hermione curled closer, slipping her thigh between his and pressing close to him, and Harry's warmth moving against him from behind, he couldn't help but get caught up in it. It was almost a blind, urgent need between the three of them, as if something was pulling them toward this and the only way out was to push through, to feel everything and touch and taste as much as possible. Harry groaned, rocking against him, and let go with a final shuddering thrust - and Ron could feel every sensation, every ripple and pulse that flooded through Harry - and he could feel how Hermione felt it and it was just too much for them both, pulling their climaxes from them in a searing wave that left them breathless.

"Oh," said Hermione again, sighing softly against Ron's chest as she snuggled closer. Harry panted softly against his shoulder, and Ron let his eyes fall shut, the pain in his arm having receded to a dull ache in the wake of the warm contentment that made the rest of his body feel as if it were humming.

"That was..." Ron began, and then couldn't get his brain to form any sort of coherent words.

"Brilliant," Harry mumbled, his lips tickling Ron's shoulder.

"I'd still really like to know if this spell works," Hermione said, having come back to her senses. "I mean, we know it does something, but I do hope it works for its intended purpose - after all, I went to an awful lot of trouble to locate these spells and research the design and mix up the ink and -"

"Hermione?" said Harry, and Ron could feel him shifting enough to peek over his shoulder at Hermione.

"Yes, Harry?"

"Shhhh," he said, kissing her hand. "I don't think we'll be able to get rid of each other after this, and really, that's good enough for me."