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i don't wanna give you up (i don't wanna let you love somebody else but me)

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Erin Gilbert is not the first straight girl Jillian Holtzmann has ever fallen for.

Here’s the thing: she’s good at patterns. She’s good at identifying patterns. Holtzmann isn't a mathematician but that doesn't mean she's not great at numbers and evaluating data and drawing a conclusion. She's a goddamn genius. This shit is easy in the way that people are difficult. Erin Gilbert is not the second or even the fifth straight girl Jillian’s ever fallen for, and it’s kind of getting to be a problem, except when she sees Dr Erin Gilbert, she thinks, maybe, this woman might be a statistical outlier. Nobody can wear that much tweed and be straight, surely. And she keeps trying, hopefully, to believe that, until the Kevin Crush makes it pretty fucking clear that it’s a losing bet. No big. Jillian is used to this, after all, and it’s totally definitely not going to be a problem at all.

It is. It is a massive fucking problem. The problem, specifically, is that Erin Gilbert is a crush she can’t get rid of. Gilbert is uptight in a way that makes Jillian want to get her unbuttoned and reeled right in. Erin talks to herself when she’s doing her calculations and she always has whiteboard pen smudges or coffee stains or both on her sweater and she’s a terrible dancer and Jillian cannot stop watching her. She likes margherita pizza and nice shoes and incomprehensible shirts that make Jillian’s skin itch just looking at them, she shares words about her feelings like it’s easy, her fringe is always too long and she chews her lip and her fingernails and her pen and anything else she’s fiddling with while she’s reading. Jillian can’t help but look, chewing her own lip in solidarity because she can’t exactly chew Gilbert’s, as nice as that would be. It’s fine. It’s just a crush. Any moment now, Jillian will dedicate her time to building that new reactor core and the whole Erin thing will totally fade.

And then they move into the new headquarters, where it turns out they totally have living space that’s not just ‘the spot under the workbench where Holtzmann has a pile of blankets that are always a little warm from radiation’, and Jillian gets to discover how Erin wears her bathrobe over her clothes and doesn’t brush her hair in days and is absolutely a glorious hot mess of a person when she’s not trying to conform to the twin expectations of academic respectability and compulsory heterosexuality. Jillian tries to treat this development as a hopeful sign for the Kevin Crush to be winding down, except that Erin still chokes on her own spit whenever he walks by or does something with his muscles, and honestly: Jillian’s not really sure whether it’s more distressing that the Kevin Crush exists at all or just that she doesn’t understand it. She’s used to understanding things. She wants, a little, to take this apart and reconstruct it so she can figure it out, except she was nine when she first tried to do that with her friends having crushes on boys. It didn’t work then and it probably wouldn’t work now. Distressing.

“If it’s any consolation, she’s like ninety-five percent probably not completely straight,” Abby says, quiet enough Erin probably won’t hear, and passes Jillian a milkshake. When she takes a sip, it turns out it’s one of the peanut butter ones from that place uptown, which means Jillian’s face has been doing a thing for long enough that Abby’s noticed. Peanut butter milkshakes only appear when Jillian is particularly miserable.

“Inconclusive,” Jillian mutters. “More evidence required. Statistics undocumented. Unscientific, Dr Yates.”

“We made out in junior year,” Abby offers. “We called it ‘practice’ but I’m pretty sure it wasn’t.” Jillian drinks her milkshake, and doesn’t say anything, and Abby bumps her shoulder against Jillian’s like she sympathizes. “We could fire Kevin,” she adds, and Jillian wrinkles her nose.

“We can’t fire Kevin,” she says, “he’s almost figured out email.”

“No he hasn’t.”

“No,” Jillian agrees, “he hasn’t.” They still can’t fire Kevin. She’s kind of got a soft spot for him, like how someone can be not objectively a dog person but still find a puppy endearing, come on, people can appreciate puppies without wanting their friends to want to make out with those puppies, she’s just looking out for Gilbert, is all.

“Yeah, if ‘looking out’ means with your mouth, Holtz,” Abby says, poking her in the ribs, and oh god, oh fuck, Jillian’s brain-to-mouth filter is gone again. She sighs, very deeply, and rests her head on Abby’s shoulder. Abby pats her hair a little. Her fingers are greasy from the popcorn she’s been eating, but that’s okay. Jillian’s pretty sure she hasn’t been able to wash all the slime out after that last time, anyway. She chases the last of her milkshake, sucks air through her straw loud enough that Erin and Patty both look up, and lounges in her chair more deliberately. Erin frowns. Looks back at her work, taps her pen against her teeth. She's got ink on her mouth. A pattern, Jillian thinks. Statistically, a problem.

“I don't have time for this,” Jillian tells Abby. “I'm building a new reactor core. Something for medium to large scale poof. Maybe a little mayhem.” Abby smiles way too kindly.

“Yeah,” she agrees, “okay, Holtzy,” and Jillian should resent it, it's pandering and condescension of the worst kind, except Abby is her first and best friend and she was there for inconvenient crush three through five, so Jillian is okay with giving her a pass on it just this once. Plus, she gives good intel on Gilbert. It's worth knowing. Like ninety-five percent is a good figure to start from.

Inconclusive, she thinks, and pokes at the machinery in front of her just to see if it explodes.


The rebuilt core is a success. Kind of too much of a success. Jillian only burns off her eyebrows a little bit, but they trap four class-three apparitions and Erin is fucking radiant with the concept of provable scientific methods and documentable research opportunities, so honestly Holtz is okay with sacrificing eyebrows for the greater good, or at least for a chance to see Erin smile like that again. She pulls her goggles down to hide the damage, and when Abby and Patty come in with Thai takeout and a lot of wine, she thinks, yeah, okay, and climbs up onto the rooftop with the others.

Three hours later, Erin has stopped using a glass, is swigging wine straight from the bottle, and Patty and Abby share a glance that is way too fucking obvious before they disappear off downstairs like they're giving Jillian a chance to make a move, or something. It's unlikely, shading to not gonna happen, Yates, Jillian has got some self-respect and some memories of college and the only thing worse than crushing on a straight girl is trying to kiss on said straight girl when you're both too drunk for good decision-making or factual assessment.

“Hey,” Erin says, suddenly hyperfocused in a way that is very difficult to cope with. “Holtzmann. What happened to your eyebrows?”

“Nothing,” Jillian says, and then amends the statement. “Transfer of potential energy to heat and shock wave. Larger poof than expected. I. I was. In the line of fire.” Fuck, this crush is the worst, she can’t even talk to Erin like a normal human being. She grins, very wide, tries to cover it. Erin frowns at her, squints at her face. Drags her lip into her mouth, frowns harder like she's thinking. She's got a smudge of penang curry at the corner of her mouth, and when she leans in, mouth falling open, her teeth are stained red from the wine. Her hair is wind-ruffled in a way Jillian wants to smooth out, or mess up more. Both. Neither. She watches Erin catch her lip under her teeth and release it, once, twice, a nervous tic that happens in slow motion. Erin's got her forehead resting against Jillian's. She's golden through the lenses of Jillian's goggles.

Jillian doesn't drink very often. This is why, she thinks, her- her thoughts get all non-linear in ways she doesn't follow, and it's upsetting, and she's got a lot of pattern recognition happening in ways she'd rather it wasn't happening. Apophenia. Pareidolia. She sits there on the rooftop, still and quiet, listens to Erin's breathing and it's like listening to the EVP, searching for meaning in every hitch of Erin's breath.

“I don't,” Jillian says, enunciating very precisely, because this is important. “Understand. You. People.”

“Generally or specifically?”

“Both,” Jillian shrugs, and Erin sits back, tugs Jillian down so they're slumped side-by-side looking up at the sky. Holds the bottle to Jillian's mouth so she can sip, except she tilts it too far, pours wine in a long line past Jillian's mouth down her chin and throat.

“Oh shoot, I'm sorry,” she apologizes immediately, and Jillian has to blink a little.

“There's wine in my bra,” she says. Erin flushes hot with embarrassment.

“God, I'm so- jeez, god, Holtz, sorry, I'm a mess.”

“You will be tomorrow,” Jillian agrees, and grabs Erin's hand, squeezes her fingers tight. Lies still like maybe Erin won't move. Is Erin breathing louder? Pareidolia again, Jillian's mind reacting to stimulus. Perceiving a familiar pattern where nothing exists.

This pattern exists. This pattern is familiar, alright. This pattern is Jillian wanting unobtainable women, eating herself up about it, and probably it would have passed by now if it weren't for Erin Gilbert and her hot mess self, her wine-stained mouth and warm hands and the way she looks at Jillian sometimes like she's surprised by everything about her. Everyone is surprised by Jillian. Erin looks like maybe it's a good surprise, is all.

Random data, Jillian thinks to herself, inconfuckingclusive, and very deliberately falls asleep right there on Erin’s shoulder, the two of them side by side on the rooftop under the open sky, because she can't deal with this right now but she doesn't want to do anything else.


When she wakes up, she's alone but Erin has draped a sweatshirt over her, and Jillian touches the cotton material of it for a long time, watching the sky lighten with dawn. Looks at the clouds like the shape of them will give her some answers. Her mouth is fuzzy, and she desperately needs coffee, and she can't help but slot the sweater data point into her mental collation of important statistics.

“You drooled on my shoulder,” Erin says when Jillian shows up down in the kitchen. Jillian shrugs.

“You spilled wine in my boobs,” she replies, “that makes us even,” and Erin groans all loud and heartfelt. Her eyeliner is smudged and she's in her bathrobe over sweatpants and she looks like she is deeply regretting everything about her life. Jillian thinks maybe today is not a day for making loud noises in the lab. She pours herself a coffee, and tentatively pats Erin's hair the way Abby does to Jillian sometimes. Inputs the noise Erin makes, the way she pushes her head into Jillian's hand and sighs all pleased and soft, straight into the dataset. Still inconclusive, maybe, but reaching a shape Jillian can see if she squints. Apophenia, maybe. Maybe not.

“Hey,” Erin says three days later, “you’re wearing my sweater,” and Jillian frowns down at it as if she genuinely hadn’t noticed.

“Am I?” she asks. Looks up at Erin and smiles, all her teeth showing. Winks, just to test a theory. “You want it back?”

“What, like, now?” Erin says, startled. A blush starting at her collarbones and working its way up. Data point, Jillian thinks, and shrugs. Tugs the cuffs down over her thumbs. Erin reaches out, touches the hem of it, and then, uncharacteristically, doesn’t pull her hand away. Leaves it resting there, just not quite on Jillian’s hip. Another data point, Jillian thinks. Getting less inconclusive by the minute. The shape of things becoming clear, like that face on Mars. The Virgin Mary in burnt toast. Erin's smile in the formation of smoke clouds.

“I guess I found it in the laundry,” Jillian tries, and Erin tilts her head sideways, steps in closer.

“No, you didn’t,” she says. Hand tightening. Pressure evident. Jillian’s breath ratchets up.

“No,” she agrees, “I didn’t.” The sweater smells like Erin’s perfume and a little bit like sweat and now probably like solder fumes, and Jillian doesn’t want to give it back, she doesn’t want to give it back at all.

“It suits you,” Erin says, “you should wear my clothes more often,” and that’s a terrible concept, Erin’s clothes are terrible, Jillian blinks and blinks at her in dismay. Pushes her glasses up so she can see Erin’s face under natural spectrum, and Erin is really very close. Jillian feels her eyes go wide.

“Your clothes are the worst, Gilbert,” she says. Leans back on her elbows, twists her mouth into a sideways smirk. She knows how to do this, she’s done this, it’s just. Her heart is pounding inconveniently right now. Elevated heart rate, pressure in her chest. Could be paroxysmal supraventricular tachycardia. Unlikely. Hypothesis: her heart is going very fucking fast because Erin Gilbert is touching her. Erin Gilbert is looking at her with an expression. The expression is interest. Reasoning: sound but confusing.

“Like you can talk,” Erin tells her, as if she can’t hear all of this shit running through Jillian’s head, “you’re wearing a tie over an MIT sweatshirt.”

“You love it. You love my ties.”

“I do,” Erin agrees, and grabs her tie, and yanks her up and in. Heart rate escalates. Surely Erin can hear it, Jesus. Jillian’s lips part, involuntary, and Erin looks determined and shit-scared in about equal measures, and Jillian didn’t feel any of this buzz of absolute terror-perfect adrenaline when faced with an actual apocalypse, but in the fact of Erin Gilbert holding her by the throat, apparently a physical response is necessary.

“I thought you were straight,” she says. Tilts her head back so she can keep looking at Erin. “But I hoped you were interested.”

“I'm not,” Erin says, intent on Jillian’s mouth, and Jillian frowns.


“Straight,” Erin clarifies, and touches her thumb to the dimple in Jillian's cheek like it's very necessary to check that it's there right now. More pareidolia. Not pareidolia. A pattern of Erin moving closer. The data supports the conclusion. Jillian feels dazed by it, lungs tight. Jesus god she wants this so much she can feel it pressing up behind her teeth. Dataset complete, conclusion: Erin Gilbert is making a move on her. Drops her glasses back down, because she can feel her pupils dilating, and it’s. Distressing. No. Arousing, yeah, that’s the word she’s looking for.

“So, is this where we do kissing?” Jillian asks, very hopefully. Are you hitting on me? Can you confirm my data?

“Yeah, Holtzmann,” Erin says. Licks her lips, the dry patch where she’s always sinking her teeth into her bottom lip. “This is where we do kissing.”


Erin Gilbert does not kiss like a straight girl. Erin Gilbert kisses Jillian like she’s been thinking about it, like every time she chews her lip she’s been considering how to lick into Jillian’s mouth in exactly the most calculated angle for maximum breathlessness, and yeah, okay, yeah, Erin's a physicist, for shit’s sake, the science of matter and energy and the way they act on each other, and the way they act on each other is fucking excellent. Erin gets her hands in Jillian’s hair, and backs her all the way up against the workbench, kisses and kisses her, and Jillian’s got to admit, her theory about statistical outliers is gaining traction by the second right now.

“What happened to the Kevin Crush?” she asks, because she is still curious, and Erin makes an impatient noise. Gets her hands under the sweatshirt, and squeaks when she discovers Jillian’s bare skin.

“You happened to the Kevin Crush,” she says like it’s obvious. Oh. Oh. “Plus,” Erin adds, “he thought my name was spelled A-A-R-E-N. Turns out that was the last straw.”

“Valid,” Jillian agrees. Cants her hips up against Erin’s. “Hey, is that a Swiss army knife in your pocket, or are you just happy to see me?”

“Oh my god,” Erin says, looking vaguely scandalized, which is frankly fucking ridiculous because she’s still got her hands up Jillian’s sweater. Erin’s sweater. The sweater that’s on Jillian’s body, ownership undetermined.

“I have a bed under my workbench,” Jillian suggests, and Erin pinches her side.

“You have a pile of blankets under your workbench,” Erin says, and pushes her down into the third-hand couch instead. Slides her hand up and up under the sweater until she’s cupping Jillian’s breast, and Jillian makes an embarrassing noise.

“You,” she says. “You’re. Confusing.” And seriously, this is terrible, Jillian knows how to do this, she’s a goddamn expert in her field, she needs to take Erin Gilbert apart to figure out how she works and then spend like six hours putting her back together again, maybe.

“You're a mad genius nuclear engineer, Holtz,” Erin says. “I think you can work it out.”


Erin Gilbert likes the scientific method. Experiments repeated until hypothesis proven. Jillian likes datasets and results, and small-to-medium explosions, and the taste of Erin’s skin right in the curve of her neck. The combination is. Not incompatible.

It turns out, when Jillian twists her fingers just right and bites Erin hard enough to leave a mark and grinds her palm right up against Erin's clit, Jillian can cause a medium-sized explosion in the form of Erin's breath stuttering out, a vacuum of sound, and then her voice, god, her voice.

“Right there don't stop don't stop don't stop,” and Jillian wasn't planning on it, scientific research involves repeating action until results confirmed, she has to make sure this is not a statistical outlier. Or is a statistical outlier, maybe. Pattern of straight girl crushes: debunked.

Three orgasms later, Erin's fringe is sticking damp and sweaty to her forehead and she's working her hands into Jillian’s pants and then sliding down to her knees and just pulling Jillian's pants right down.

“Can I pull your hair,” Jillian asks, and Erin gives her a quick grin before pushing Jillian’s thighs open. She eats Jillian out sloppy-thorough, like she maybe hasn’t had a whole lot of experience but is extremely determined regardless, and when Jillian comes her ears pop like the pressure is equalizing, the same way they did in the Aldridge Mansion.

“Jesus,” she says. Catches her breath. Stares up at the ceiling for a minute or two. Her hands are still in Erin’s hair. “Are you a ghost?” she asks, just to check, and Erin kisses the inside of her thigh, grazes her teeth over the skin.

“I don’t think so,” she says, serious, and Jillian huffs out a breath.

“Okay,” she agrees. “Just wanted to check.” Drags Erin up until she’s lying on the couch again, and looks at her mouth, touches it with the tip of one finger. Bolts upright, and Erin catches her.

“Where are you going?”

“I need to run some data analysis,” Jillian says like it's obvious.

“On what?”

“The shape of your smile.” It's important, Jillian thinks. If she inputs enough into the dataset, finds the right algorithms, maybe she'll understand what it is that makes her heart catch. Exactly what Erin's smile means when it's this soft and unfiltered.

“You're an engineer, not a statistician,” Erin points out, and Jillian supposes that's true, so she lies back down. Squints at Erin.

“You’re an outlier,” she tells her, and Erin laughs a little, buries her face in Jillian’s hair.

“An outlier in what?” she murmurs, sounding sleepy. It’s the middle of the day, and Jillian has like fifteen different things she’s in the middle of, but she grabs the couch blanket anyway, flings it over them.

“Statistical data,” Jillian tells her. “Straight women. I got a bad habit, historically speaking.” She does, she’s got about twenty different bad fucking habits beginning with eating junk food while they do science and ending with her startling lack of concern for her own personal safety around nuclear material, but Erin Gilbert isn’t the first straight girl she’s ever crushed on, because Erin Gilbert is not fucking straight, and ain’t that a goddamn delight. Time to create new patterns, maybe, Jillian thinks. Conclusive.