This is a story I've been working on for a few weeks. I believe that the M rating is accurate, but if there are any disagreements on this point, I'll move it to and post a link here.
While I wrote this, I listened to not only the song mentioned in the text, but also the following playlist: playlist?list=PLSQ0NMJmzsk_MFWf9o0BicvU4ExVn2roP
(The best song by far is 'Defenestraight To My Heart'.)

Valkyrie had been travelling all day. A cab to the pet sitters', where Xena would be staying. Another cab to the airport. A plane that took her across the Atlantic Ocean. And now, finally, a rental car that would take her where she needed to go.
She was exhausted.
As her phone charged in the cigarette lighter, she listened to her iPod. Her playlist was comprised of music that made her think of him: mostly cool jazz, some old-school rhythm and blues, a little swing when her mood needed picking up.
Right now, the song was 'If I Didn't Care' by The Ink Spots, and a few tears ran down her face and neck.
She left the car a few streets over and walked the rest of the way, expecting to see the Bentley parked in front of his house, like it always was. But it wasn't there. He wasn't home.
There was nothing to do but duck in his porch, out of the starting rain.

Valkyrie didn't know how long she waited, but the battery in the iPod ran out. She thought about him returning; what she would say. She thought about her dog, all alone in the kennel. Then, finally, the Bentley turned the corner at the top of the street, and Valkyrie hugged herself tighter. There he was.
As the car drew close, an unpleasant thought struck her. Would he realise it was her, hunched in the doorway? Would he draw his gun, mistaking her for someone else?
The tyres rolled smoothly over the wet drive before stopping, and the engine slowly died. There was his silhouette behind the wheel. The smooth, white skull; the clean lines of his suit. As he got out of the car, he cocked his head, gazing at the stars.
She got to her feet, and Skulduggery turned. He straightened in recognition.
"Valkyrie?"
She stood and shivered.
He took a step. "Valkyrie."
She closed the distance, and her expression must have been quite moving, for he pulled her into a tight hug immediately. Valkyrie held her arms around him, feeling the wire framework that gave his suits their shape, and his ribcage beneath that. The spots of rain that landed on his clothes released the scent of the powder they'd been washed in.
"You're back," he said, bewildered.
She supressed a sob. "Looks like it."
That hug lasted a while. Valkyrie was almost afraid to let go, but when she did, he held her at arm's length and tilted his head, like he always did.
"You'd better come in," he said.

She told him about the house, about Xena, and about the unpleasantness of her journey, but the question of why she'd come to Ireland without notice wasn't raised, and Valkyrie was grateful. The mug of tea she cradled in her hands eventually grew cold, and he took it from her.
"Well, you've had a rough night, by all accounts," he said. "Did you catch any sleep?"
"With Chatty McDullard sat next to me for seven hours? Definitely not."
He gave a sympathetic nod. Behind him, the kettle switched itself on and started boiling, and he darted over to stop it. Valkyrie smirked. She'd forgotten that about this house. How long had it been since he'd plugged that kettle in?
"There's still the spare room," Skulduggery offered. "I had it cleared out recently."
"Thank you."
"I'm a little surprised you didn't get Fletcher to bring you back."
She grimaced. "I don't want him to know where I am."
"Ah." There was a moment of mutual reflection as the clock on the wall ticked louder than ever. "Do your parents know you're here?"
"No." Valkyrie sighed. "I don't think I'm ready to face them yet."
"Can you see a time when you will be ready?"
So as not to provoke an argument, Valkyrie nodded. She nodded in a way that implied an unwillingness to discuss it further. Once again, Skulduggery mentioned the spare room.
"What about you?"
"I'll be down here, looking through some Sanctuary files," he replied. "We can talk in the morning."
"Thank you," she said again.
For a moment, she considered asking what cases he was working on. But he was right. She needed to sleep, and this was something that could wait until the morning.
She hugged him in the centre of the kitchen, lingering in his embrace. Then she said goodnight, climbed the stairs with her overnight bag, and found the spare room. There were boxes piled all around, and a broken lamp on the chest of drawers where Skulduggery kept his spare shirts. In spite of the chilliness of this room, she slipped into her nightgown and left her clothes crumpled at the foot of the bed. She huddled beneath the covers until it was warm enough, and then stretched out her arms, staring at the pattern of the ceiling.
Tomorrow they'd talk. Tomorrow she and Skulduggery would put the world to rights.

Alice was dead.
Alice was lying on the ground, not breathing, not moving, and Valkyrie's efforts to revive her didn't work.
That horrible laughter. Darquesse's laughter.
And someone was there, someone was shaking her shoulders and she thrashed, tried to release the grip
... and she was back in the room, Skulduggery standing over her.
For a moment she stared into his empty sockets, then fell back against the pillow. What an idiot, she thought.
"I had a nightmare."
He nodded and spoke softly. "Never mind. Never mind. You're all right."
The room was cool and dark, save for a strip of light from the half-open door. Suddenly self-conscious, she pulled the covers close and sat up.
"Was I sleep-talking?"
"Well," he admitted, "sleep-screaming."
"Oh. I'm sorry."
"Nonsense. You didn't disturb me."
She put a hand up to her head and felt the mess of hair. Sighing, she leaned over to grab her bag. Her right hand found her hairbrush and lifted it out.
"Don't you sleep at all these days?" she asked, working the brush through her tangles. "Meditate, I mean."
"Not often. It depends how many cases I'm working on." He perched on the edge of the bed. "I've found the recent cases are substantially less demanding than our last ones."
She liked the way he said that.
"Would it help if I stayed here," he asked, "until you fall asleep again?"
"It might," she said.
He moved around the bed and sat on her left side, which left enough room for her to stretch out. Her head was heavy; her mind was tired. But he just sat, watching her.
"Lie down."
He did. "Are you warm enough?"
She was.
"What do you normally do to get to sleep?"
"Take a tablet," she admitted, "but I left them at home."
"Ah. Anything else?"
For just a moment, Valkyrie deliberated. Could she tell him? Not many people understood the concept.
"Have you heard of ASMR?"
"No. What is it?"
"It stands for Autonomous Sensory Meridian Response. It's a physical reaction to certain sounds, like whispers, clicks, things like that. You get a tingle down your spine..." She paused, wondering how to explain it. "I'll show you."
She fetched her mobile phone from her jacket pocket. Bringing up her favourite ASMR video would burn through her mobile internet, since Skulduggery only had a wired internet connection, but she didn't care. She held the spare earbud from her earphones to the side of Skulduggery's head.
They watched in silence for five minutes.
"So," Skulduggery said, "this lady is going to brush and oil her friend's hair for thirty minutes?"
"Pretty much."
"Well, I can see how it would be relaxing to watch." He made a throat-clearing sound. "And the audio is very... It certainly gets inside one's head."
She moved closer, lining up the side of her body with the side of his.
"I thought you'd like it. What with all the meditation you do."
"Yes. This is similar."
Valkyrie rested her right arm – the arm holding her phone aloft – atop Skulduggery's chest. He'd taken off the wire frame.
"I remember when I was twelve," she said, "asking you what you missed about being alive, and you said hair."
"Yes," he said.
"I suppose getting the façade helped."
"Hm."
Skulduggery reached over with his left arm (carefully, so as not to block the screen) and tucked some of Valkyrie's hair behind her ear. He repeated the motion, slowly this time.
"Do you mind?"
Valkyrie murmured happily.
"Sorry?"
"No, I don't mind."
She closed her eyes. His fingers ran through her hair again and again; sometimes drawing it straight out from her head; sometimes raking the lengths against her bare shoulder. The phone fell behind Skulduggery, forgotten. Then, his bony fingertips pressed against her scalp. He lightly scratched, massaged her head, clasped handfuls of her tresses and twirled the very ends. If she'd been a cat, she'd most definitely be purring.
But it wasn't enough.
So she propped herself on one elbow and told him, ever so softly, "I've given up on sleeping." She placed her hand on the side of his skull. When he didn't resist, she kissed his teeth. She held it, prolonged it, until his own hand came to her jawbone. Their heads parted, and they looked at one another, as though for the first time.
"Let me have the façade," he said into her ear. "I want to kiss you."
She drew further back, allowing him to touch the symbol etched on his collarbone. A face flowed over his skull – one which had a heavy moustache – and she laughed, telling him to change it. He did, and he kissed her. Valkyrie frowned. His lips tasted waxy. But she reciprocated, sinking into the kiss, before he moved down and grazed on her neck. She felt the touch of moisture he'd borrowed from her mouth.
"Is this what you want?" he asked.
She gazed into his eyes. "It's the reason I came."
Making love was strange, but only as strange as she'd imagined, all those lonely nights. He was a skeleton – there was no warmth, no breath, no rise and fall of his torso. It was, as it had always been, about the small movements he made, and she gave herself over to them.
Afterwards, she lay beside him again. Skulduggery ran his hands over her skin, where there were indentations from his own ribcage. She laughed.
"I know what you're thinking," she said.
"And what would that be?"
"You're thinking, 'she doesn't exercise as much as she used to'."
Skulduggery shrugged. "Actually, I didn't notice."
"What are you thinking about?"
"I'm just enjoying the way your hair hangs between my ribs."
She smiled and moved her head, dragging the hair across. "How's that?"
"That's just fine."
As Valkyrie caressed his bones with her locks, she found herself singing that song by The Ink Spots. She felt him smile as he hummed the tune, accompanying her perfectly.
"You know it," she said.
"Of course I do. How do you know it?"
"'The Shawshank Redemption'."
"I should have guessed."
He continued to hum as Valkyrie brushed him with her hair. For the first time in many months, she felt at peace. Even nowadays the memories of her actions would return to haunt her anew. It was the most affirming thing, to be close to somebody who'd seen her at her most wonderful, and her most terrible, and loved her all the same.
"Are you ready to sleep?"
She shook her head. "I want you to feel what I felt." She stroked the length of his forearm; he liked to be stroked there, along with his breastbone, pelvis and spinal column.
"You don't even know if I'm capable of that."
Valkyrie called upon her newfound magic; the magic that Skulduggery found to be so mysterious. With her right hand, she sent a flash of energy along his spine, shooting between each and every vertebra. The sensation caused him to stiffen and gasp.
"Surprise," she said.

When Valkyrie woke, the spot beside her was empty. The heavy curtains were still drawn across, obscuring the midday sun. The air was a little warmer. He must have turned up the central heating.
She pulled her jacket on over the nightgown and padded downstairs. She listened for any noise, any sign that he was still in the house. When she reached the kitchen, a handwritten note awaited her.
Valkyrie held it up to read it.

Dear Valkyrie,
The Sanctuary called me in; I didn't want to wake you.
Part of me is convinced that you'll be gone by the time I return. The decision is yours to make, of course. You must be troubled by the prospect of facing your parents. and your sister. The time will come to make up for your mistakes in earnest, but to make that happen, you'll have to be a part of their lives.
I'm sure I've said all this before. Regardless, I want you to think of this place as your home, and think of yourself as my partner. You will always be a part of my life, and you will never lose me.
There's bread in the cupboard to your left.
Skulduggery.

Valkyrie was thrown. She read the note many times. She read it in his voice. She read it, hearing the music from last night. Then she shed as many tears as she could stand.
The prospect of returning to Meek Ridge was, she knew, inevitable. And yet, here it was, this letter from Skulduggery, offering her a form of sanctuary and understanding.
He loved her. She loved him back.
Until the end.
Valkyrie folded the paper, very carefully, and placed it inside her jacket pocket. Then she turned to switch the faulty kettle on at the wall.

The End