Crossover, Good Omens/His Dark Materials, Adam/Lyra, revolution
'You can walk through worlds! You can!" Lyra's slim frame was shivering with rage. 'You don't have to worry about windows or specters, you just slip past like an angel - but you've got flesh - you...' And she slapped him, hard, and again, and he wrapped his arms around her and pulled her down against him, small breasts tight against his wide pale chest. With another yowl of rage, she tried to lift herself off, but he held her still, hissing "shh" into her ear until she lay still and wept.
'Lyra, sweet, I thought you'd be pleased,' he said. 'I heard you left friends in my world... I could take them messages.'
Lyra's crying subsided slowly, like a tide running out into a trickle, and she shivered against him. Sorrow made the air colder, just like passion had made it warm just such a little while ago.
She raised herself up on her arms, her knees still resting on either side of his waist, her hair falling down to hide the gaze that passed between the two of them, like curtains. He could barely see her in the faint moonlight, and couldn't judge her expression. Lyra reached between them, slowly, deliberately, and began to stroke him. The touch was a surprise, and pleasure jolted through him immediately. He lifted his hands to stroke her hair, stroke her breasts, her face, touching her sweet pliant mouth with his fingers. He was hard within a moment, and he slipped one hand down into Lyra's (still?) moist flower, running his thumb across her pearl, and feeling her react instantly, her body snapping tight like a bow.
'I hate you right now,' she said. 'You deserve it,' she added in a murmur. He didn't know what she meant, any more than he understood why she'd been crying the moment before.
Lyra lifted her hips and settled down on Adam's length, pushing herself down, feeling it fill her up with pleasure, and thought of Will. She closed her eyes tightly, imagined Will's face as it would be now, older, but still with those same straight eyebrows and determined jaw. A little like his father, a little like his mother, whom Lyra had never seen - and something that was just himself, something Lyra loved more than anything in the world. She imagined his hands, his sighs, his kisses, years ago, remembered the thrill of love, and stifled her sobs as she rode Adam, faster, faster, chasing Will's image.
Afterwards, Adam lay back on the bed, and Lyra lay on her side, curled up, thinking. 'Take me with you,' she said.
Adam, startled, saw her face clearly in the moonlight; the tears were gone, and she looked determined enough to intimidate the Devil himself. 'I can't.'
'Find a way. Tear the heavens apart if you have to, but if there is a way, you take me with you to your world, and then bring me back again.'
Adam's mind was swirling, already trying to find a solution to the suggestion, though he should still be protesting. 'There are rules about that sort of thing,' but almost before the sentence was out, he was laughing, and after a moment, so was Lyra. Neither of them were ever very big on rules.