The first thing I noticed was the way he looked at her.
It wasn't particularly obvious. Just a glance across the room as she laughed at something I'd said, his eyes lingering a moment longer than necessary.
I smiled into my wineglass.
They were a beautiful couple, with the easy confidence of people who know themselves and are comfortable in their own skin. She was elegant, with dark hair falling loosely around her shoulders and a laugh that made you want to join in. He was handsome in a slightly rugged, distinguished way I've always found appealing, with a warm smile and a wonderfully dry sense of humour.
But what intrigued me most was their chemistry.

The little touches. The private jokes. The way his hand occasionally settled on her knee, and how she'd lean towards him when he spoke. They were clearly very much in love, and I found that captivating.
As the evening unfolded, I became increasingly distracted by these small displays of affection. When she reached across him for the wine bottle, his hand settled instinctively against her back. Later, as she laughed at one of his jokes, she rested her hand on his thigh without seeming to realise she'd done it. I wondered whether either of them noticed how often they touched.

There was something lovely about it. The kind of intimacy that can't be manufactured.
At one point, I told them they were my favourite kind of couple.
"The kind who actually seem to like each other," I explained.
They laughed, and she gave me an amused, slightly suspicious look.
"Are you flirting with us?"
"Would that be terribly inappropriate?"
Her smile suggested she didn't think so.
I liked her enormously. There was something open about her, a warmth that made conversation effortless, and beneath that elegant composure a playful streak I suspected she didn't always let people see. Her partner seemed content to let the two of us entertain ourselves, though I noticed he was watching our exchanges with considerable interest.
We opened another bottle, and somewhere along the way the conversation turned to massage. They were both fond of it, although he complained, with theatrical suffering, that he was usually the one doing all the work.

Naturally, I couldn't let such an injustice go unaddressed.
I mentioned that I happened to have some lovely massage oil, a perfectly comfortable bedroom, and nowhere else I needed to be that evening.
There were amused glances and a moment of consideration. She looked at him, smiling.
"Oh, go on. You deserve a little pampering."
And that was that.
He followed me into the bedroom while she collected our glasses. The room was softly lit, the bedside lamps casting a warm glow across the freshly made bed. I put on some quiet music and took a bottle of oil from the drawer. He seemed amused by how prepared I was.
I assured him that I simply liked to be a good hostess.
His partner appeared moments later, carrying our wine and looking far too entertained. She wondered aloud whether she ought to be worried about leaving us alone.
"Terribly worried," I said. "Although you're more than welcome to stay and supervise."

She decided that sounded like an excellent idea.
He pulled off his shirt and stretched out facedown on the bed, head resting on his folded arms, while she settled against the pillows beside him.

I warmed some oil between my palms and set my hands on his shoulders.
He relaxed almost immediately.
There was something satisfying about the way the tension gave way beneath my fingers. His shoulders softened, his breathing slowed, and every so often he sighed in appreciation. His partner teased him about becoming far too accustomed to being spoiled, and I enjoyed their banter. Even their teasing was affectionate, full of references and shared memories that spoke of years together.
After a while, I glanced across at her.
"Come a little closer."
She raised an eyebrow, clearly wondering what I was up to, but obliged, settling beside his head, close enough to reach him without disturbing me. She brushed a strand of hair from his forehead and leaned down to kiss his cheek.
He turned his face towards hers, smiling.
It was a simple moment, but I watched their expressions change. The teasing fell away, replaced by something softer and altogether more intimate.
She kissed him again, and this time he lifted his head to meet her.
I kept working across his shoulders, watching with growing fascination as their attention drifted from me and towards one another. Her fingers slipped into his hair. He reached for her hand. Then, almost without thinking, he rolled onto his back and drew her down against him, and she laughed softly as she settled across his chest, her dark hair falling around their faces.
I quietly withdrew my hands. Neither of them noticed.
I moved to the chair at the foot of the bed and took my wine with me. It seemed only polite to give them room.

Their earlier tenderness hadn't disappeared, but something had changed. The kisses grew deeper, hungrier, and there was a new urgency in them, a growing impatience that made the little pauses and affectionate smiles all the more compelling. His hands moved down her back and over the curve of her hips, and she pressed closer, a low sound escaping her that I felt somewhere beneath my ribs.
She sat up, straddling him, and he looked at her as though he'd never seen her before. She pulled her shirt over her head and dropped it off the edge of the bed. Her bra followed. His hands came up to cup her breasts, thumbs circling her nipples until they hardened, and she let out a shaky breath and rocked her hips down against him. Through his jeans I could see exactly how much he wanted her.
I'd stopped drinking my wine.
There was nothing rehearsed in any of it. It was hunger and familiarity in the same breath, and the two together were more erotic than anything I could have staged. He caught her around the waist and rolled her beneath him, and then his mouth was on her throat, her collarbone, her breast, drawing a nipple between his lips and sucking until she arched off the mattress and tangled her fingers in his hair, saying his name like a question she already knew the answer to.
The rest of their clothes disappeared in a flurry of impatient hands and breathless laughter. Her underwear went over the side of the bed. His followed. He was thick and hard and beautiful, and she wrapped her hand around him at once, stroking slowly, her thumb spreading the bead of wetness at the tip. He groaned against her mouth.
He kissed his way down her stomach, and she parted her thighs for him without being asked. I had the perfect view of his mouth settling against her, the slow, deliberate stroke of his tongue, the way her hips lifted to meet it. Her fingers curled into the sheets. The sounds she made were low and unguarded, and I could hear how wet she was, and I pressed my thighs together in my chair and said nothing at all.
He slid two fingers inside her without lifting his mouth, curling them in a way that made her gasp, and her whole body began to tremble.
"Please," she said. "I want you inside me."
He didn't make her wait.
He moved up over her and she guided him to her, her legs wrapping around his waist, and he pushed into her in one long, slow stroke that dragged a cry from both of them. He stayed there for a moment, buried to the hilt, his forehead against hers, and then he began to move: deep and deliberate at first, her hands sliding over his back, her heels pressing into him, urging him on.
Then not slow at all.
The bed began to protest in time with them. Skin met skin with a wet, unmistakable sound. Her breasts moved with every thrust, and her breathing broke into short, helpless cries, yes and there and harder, and he gave her all of it, gripping her thigh and angling her hips higher until her voice cracked.
I was no longer pretending to be a bystander. My free hand had found its way beneath the hem of my skirt, and I pressed down and slowly, quietly, began to move. Neither of them noticed. I doubt they could have noticed anything.

He pulled out and turned her onto her stomach, and she came up onto her hands and knees with a breathless laugh that turned into a moan as he pushed back inside her. His hands closed around her hips. Her face dropped to the pillow. I watched him fuck her, watched the muscles shift across his back and her dark hair spill over her shoulders, and I slipped my fingers beneath the silk and found myself wet, swollen, and entirely out of patience.
He reached around to touch her, and she shattered. It was a long, shuddering orgasm that tore his name out of her and clenched her around him until he swore, low and rough, and slowed to hold her through it. I came with her, just from watching, biting my lip to stay quiet, my thighs shaking against the arms of the chair.

He lasted only a few strokes longer. He gripped her hips, thrust deep, and came with a groan that seemed to come from somewhere very far down, his whole body locked against hers, and then he collapsed over her, and they both fell into the sheets in a tangle of limbs and ragged breath.
I withdrew my hand and picked up my wine.

He pulled her into his arms, and for a long while they simply held one another, flushed and smiling, her fingers tracing lazy patterns on his chest. At last she looked over his shoulder at me, bright-eyed, her hair a wreck, and raised an eyebrow.
"Terribly worried," she said, in a passable imitation of my voice.
I lifted my glass to her.
"Entirely justified."