Disclaimer: Obviously this flawless show is not mine.
She's in the filing cupboard, door just ajar when she hears him come into the office and close the door behind him. At first, she doesn't think anything of it and it's probably just Josh doing his wall-calming thing again. She keeps flicking through files, about to call out and ask if he knows where the LOG summit file has disappeared to when she hears it: the soft, low hiccup that definitely isn't Josh; the familiar throaty murmur that could only belong to Amy.
There's a rustling of papers falling to the ground and Josh groans. It's not familiar though, not in the way he groans at her when she asks too many questions or tells him he should stop eating junk. Different, not like he's in pain but- oh. Oh.
She's halfway through wondering how long they're going to take and if she should just walk out now before they really get started when she hears him breathe in sharply. An involuntary shiver courses through her and something sinks low and warm, to the bottom of her stomach.
Stop, she thinks. Shakes her head and takes a quiet breath, straightens herself up.
Amy giggles outside and Donna can just see the smirk sliding so easily onto cherry-red lips. Josh's hands gripping Amy's waist possessively, clutching tight like he's afraid she'll slip out of his grasp.
Donna wonders, as she leans back against the wall and reaches down to scratch absent-mindedly at her knee, whether Josh would hold her like that. Whether he would be rough, pulling her to him and biting against her neck, or if he'd slide his hands down to her waist, lift her chin up to him tenderly and lick against her bottom lip, questioning.
She fingers the hem of her skirt, nails biting into the wool. There's the soft swish of a shirt falling to the floor and Donna doesn't think about the mess they're making or the fact she'll probably have to go to Josh's apartment to pick up a new suit later. Instead she slides her fingers inside the hem, drags them up the inside of her skirt, the outside of her leg.
Stop, she thinks.
And then she stops thinking.
Her fingers inch further up her leg, moving to the inside of her thigh and grazing the edge of her underwear, running light circles against her skin.
She hitches her skirt up higher for better access, scraping her nails low on her stomach and dipping her fingertips down inside her underwear, can feel the heat there inches away.
For a moment she imagines these are Josh's hands sliding against her, pushing against her, and the rough edges of her fingers from sliding paperclips and typing too heavily are not her own, but her boss'.
She doesn't stop imagining.
She has to stifle a breath when she slips her index finger inside herself, pulling her lower lip between her teeth and biting down hard.
She thinks she tastes blood.
Donna can hear them outside in his office: his breath hitches and she hears the chair squeak, imagines him sitting back, zipper undone, pants halfway down his thighs with Amy leaning over him, her knee positioned between his legs and her hands squirming inside his boxers. She can see him, head thrown back and eyes shut tight and she pushes two fingers inside.
She doesn't think about the fact that listening to her boss fuck his sometimes-girlfriend in his office while she jerks off to the thought of his hands on her is probably the most screwed up thing she's done.
She heard it was better to love someone from afar than to not love them at all, she figures the same goes for lust. Or whatever the fuck this thing is between them anyway.
Amy sighs and Donna has to bring her free hand up to cover her mouth for fear she might cry out. She presses her palm against her clit, cupping herself and then shifts her thumb up to rub circles there instead.
Josh grunts louder outside and Donna's breathing shallows as she presses harder, toes curling inside her shoes like that might help release the pressure.
She comes undone to the sound of Josh's harsh breaths and Amy's hiccupping sigh. Donna pushes against the wall, the cool plaster against her back. Quietly she steadies her breathing, pulls her skirt down and wipes her fingers on her underwear as she pulls them out. Outside she can hear Josh pulling his shirt back on and Amy speaking softly. The door to his office opens and closes with the sound of papers being tidied and stationery rearranged. A few minutes later the door opens again and Donna peeks out the opening in the door before stepping into the office and swallowing hard.