This is a bad idea.

That much Felicity knows. She's known it from the moment she had that fourth glass of wine, from when she pulled her hair out of her ponytail, from the second Oliver had taken off her glasses and put them to one side after they got steamed up while she was eating the noodles Curtis ordered, even.

Still, she's not sure if it's the food, or the alcohol, or the fact that Oliver just looks so cheerful for once, but something inside Felicity that has been coiled up for months has suddenly unfurled. Her hair is loosened, the last remnants of her lipstick licked off long ago, and when Oliver lifts her off the salmon ladder and their noses brush a little sparkle of electricity surges through her, right up her spine.

She can barely hear herself as he takes a step back, as if thinking he's invaded her space somehow. Still he has that stupid smile on his face as he says, "In fairness, you've had a little bit to drink."

Wow. Understatement much. She takes a step forward, still a little breathless from half chinning and upping on the salmon ladder.

"I've had a lot to drink," she says, and despite herself and the niggling doubt in the back of her mind, the liquid courage from the wine kicks in and she stands on her tiptoes and kisses him.

She takes him by surprise, that's for sure, but after a moment he kisses her back. He tastes of wine and sweat, and Felicity can't help but moan as he plies open her lips with his tongue. Her arms go around his neck, as she leans into him, and her hands go to the hem of his shirt, lifting it up and over his head.

Oliver turns her round, and she laughs when he fiddles with her shirt for a couple of seconds before muttering, "Can you just -" Willingly she takes it off, and he murmurs, "Thank you."

Felicity turns back around, already missing the feeling of his lips on hers. She's missed this, missed him, his beard bruising her cheeks and her jaw and setting her skin on fire, and oh God what is she doing?

Suddenly she pulls away, looks at him, and the words this is a mistake and we should stop are on her tongue but then she meets his eyes. They're full of warmth, and he's gazing at her like he's ready for whatever she wants. His eyes - a hot, burning blue - shine so bright as he smiles down at her, and it's impossible not to smile back and lose herself in him.

He lifts her off her feet easily, and she wraps her legs around his waist as he takes a step backwards and lowers himself onto the raised platform where he normally trains. He's hard for her, she can feel that much as she tightens her legs around his hips and pushes her hair away from her face so she can kiss him. Felicity pulls away, then, palms on his chest, fingers tweaking his nipple and making him groan her name. She grinds her hips against him, and the feeling of the hardness pressing into her thigh is enough to send a shiver of anticipation up her spine and a rush of arousal right to her groin.

Reaching up to kiss her, Oliver sits up, saying against her lips, "Hey, Felicity… hold on to me tight," and he manoeuvres them so he's on top of her, now. He crawls off her, pulling down her pants as he does so, and Felicity reaches behind her, takes off her bra, parting her legs, and Oliver settles between them, reaching up so he can kiss her breast. He licks expertly at her nipple and it pebbles under his mouth, and he runs his tongue right under the underside of her breast, making her gasp and arch into him.

Meanwhile his other hand moves down, to her abdomen, where it halts, and he looks up at her, meets her eyes, his gaze burning into hers. She realises that he's seeking permission, and in answer she pushes down her panties to knee level, making him duck his head and nudge his nose between her thighs, and she knows he's breathing her in, from the way he inhales sharply. Felicity can smell it too, her scent, the smell of her lust heady in her nostrils.

The bump of his nose against her entrance prompts a fresh rush of arousal to run through her, and Oliver's tongue darts out, licking a fiery stripe into her centre and then - tortuously - moving his mouth away, so he can kiss the inside of her thigh while taking her panties off the rest of the way and off her ankles. He takes his time, the prickle of his stubble burning sensitive flesh.

"Oliver…" she moans, and he looks up, then, his gaze rapturous, looking just about ready to worship her. He lowers his head, drops another kiss on her inner thigh, mouth moving upwards until finally he's at her centre. He knows how she likes it - hard and fast - and knows her weak spots like the back of his hand, that much she knows, and sure enough when he finds her clit she cries out, the sound echoing in the bunker.

Oliver lifts her legs over his bare shoulders, lapping her up, arousal pooling onto his tongue, and Felicity reaches out, takes his hand, the one resting on her knee. She squeezes his fingers, and he squeezes back, making love to her with his mouth, the flat of his tongue on her clit, not stopping until she hits her climax, until she comes so hard that she could swear she's seeing stars.

"Whoa," she whispers when she gets her breath back, and he lifts his face to hers and kisses her, so she can taste herself on his tongue. She's not used to it, to that sharp sweetness that she hasn't tasted in months, but she relishes it all the same, as she pushes at his chest so she's straddling him once more. His hard-on digs into her thigh, and she shifts a little, trying to pull down his pants.

"A little help here?" Felicity says, and he laughs, ridding himself of his remaining garments and shoes so he's as naked as her. She reaches out, palms his length, pumping him for a second, making Oliver whimper. He tries to sit up, but Felicity pushes at his chest, hard, and he lands back on the platform with a thump. "Sorry," she says but she says it with a grin and it's like he can tell she's not really sorry.

"You're fine," he replies nonetheless, amusement sparkling in his eyes. It changes to heady lust, though, as, still with her hand enclosing hm, she positions his cock against her opening, slowly sinking onto him. And she's missed this, missed the way he fills her so completely that she can't tell where she ends and he begins, the way his hands press against the small of her back and the way he thrusts into her.

When their eyes meet they share a smile, and it occurs to her as she rides out her release that he's completely at her mercy, and as he lies beneath her, supine, indolent, he's surrendered to her every touch, every thrust.

"Oh God…" Felicity mutters, "oh wow, Oliver…"

"F'licity…" His forehead is shiny with sweat, now, and as she buries her face into his neck she can taste his perspiration on her tongue as she comes a second time. She stills on top of him, and after a second he starts moving, his hips jerking up and slamming into hers. They move together, and Felicity bears the way he thrusts into her until at last he spills inside her, landing clumsy kisses on her face, on her nose and cheek and lips.

She moves off him, foot curling around his ankle, and he kisses the top of her head. She closes her eyes, then, and pretends not to hear him mouth the words I love you into her hair.

Then Felicity disentangles her limbs from his, gets to her feet. He looks up at her, crestfallen. "Was that - not okay?" he asks, and all of a sudden hurt replaces the pleasure on his features as he stares up at her.

Felicity immediately shakes her head. "I'm not going anywhere," she assures him. "I'm just - getting a blanket. You know. In case we get cold."

And sure enough she reaches out, thankful that there's a blanket on a nearby table. She lies back down, draping the blanket over both of them, and she puts her hand on his bare chest. He covers her hand with his own, linking their fingers, and Felicity wishes she could lie there forever with him.

He looks reassured, somewhat, now he knows that she's not leaving, and the previously blissful look on his face slowly returns. Oliver reaches down and kisses her, on the forehead, and Felicity closes her eyes, wishing he wouldn't, not because it doesn't feel nice but because she knows their intimacy is temporary. Fleeting. And as the haze of her orgasm begins to clear and the alcohol that's been clouding her judgement starts to fade away, she suddenly can't quite look him in the eyes as she speaks.

"Promise me you're not gonna tell anyone we had bunker sex."