Erin Gilbert had a problem. A big problem. A massive problem.

A problem that was currently squirrelled away up on the second floor of the Ghostbusters headquarters, making "revolutionary changes" to the team's proton packs.

A problem by the name of Dr. Jillian Holtzmann.

Erin wasn't sure what "revolutionary changes" actually entailed, but she was a little scared to find out. Holtzmann always went though several rounds of trial-and-error with every new addition to their ghost-fighting inventory, and Erin had had enough of being the test pilot. One of these days, she was actually going to die at the hands of Holtzmann. She just knew it.

As if on cue, a thundering explosion came from the upper floor. Erin's head snapped up from the equations scrawled on the large whiteboard in front of her. She was the only one still in the building aside from Holtzmann, who practically slept there most days. Erin didn't normally stay after dinner, but she was really close to a breakthrough in her work.

Before Erin could get to the stairs to investigate the explosion, Holtz came hurtling down the fire pole. She froze when she saw Erin.

"You're still here?" She moved her goggles to perch on top of her head and squinted at Erin.

"Yeah, I was working on—wait, don't distract me. What was that noise?"

"Ah. Yes. Are there any more extinguishers down here? I appear to have run out."

"Holtzmann! What did you do?" Erin said as Holtz strolled over to a storage cupboard with no real sense of urgency.

"Tiny thing. No biggie," Holtzmann said as she pulled various odds and ends out of the cupboard. She dropped into a crouch to examine the bottom shelf.

"It's behind the emergency blankets. Top shelf. And what do you mean by 'tiny thing?'"

Knowing Holtz, that could mean anything. That woman had very skewed perceptions of the world, sometimes.

"Gotcha," said Holtz, hoisting herself back into a standing position and retrieving the fire extinguisher from the top shelf. "And, uh…tiny, microscopic, minor…nuclear thingie thing."

"WHAT?"

Holtzmann grinned and pushed past Erin with the extinguisher tucked under her arm like a football. She bounded up the stairs, two at a time, her oversized coat fluttering behind her like a cape. She only seemed to ever move with urgency when she was A) Chasing a ghost or B) Escaping Erin's chastising. Erin jogged up the stairs after Holtz, and rounded the corner expecting to see half the building on fire.

The blaze was pretty small, though, and contained to one of Holtz' worktables. What exactly was on fire, Erin wasn't sure, but whatever it was, it was being doused in foam right now. And—oh my God, was Holtz moonwalking around the table with the extinguisher? Erin clutched the doorframe for support. She was a little out of breath—from the stairs, obviously.

Holtzmann caught her staring and winked. "See? Tiny."

Erin felt her heartrate accelerate well beyond a safe speed, just like it did whenever Holtz winked at her. It always hit her just as strongly as it did the very first time, back when she had just told Holtz and Patty about the ghost that haunted her every night for a year. Erin still dreamt about that wink, and all the ones since then. They made her bones melt, and her knees shake, and her palms get all clammy and gross. Her little bisexual heart couldn't take it.

"Tiny," Erin repeated. Her voice sounded strange to herself, like she was underwater.

Holtz finished spraying down the fire, which was down to embers and some charred hunks of metal, and waved away the lingering smoke. She tossed the fire extinguisher onto the table with a thunk. "I think perhaps we need to acquire some new extinguishers."

"Yes. Yessiroo. Yeppers." Erin really wished she didn't turn into a bumbling idiot every time Holtz did something hot. Which was more often than you'd think.

Luckily, Holtz was distracted. She put her goggles back on and circled the table, staring down at the mess. Then she took a seat on a rolling stool and leaned back into her hands like there was a chair-back behind her. All Erin could think about was how much core strength that must take. Oh no. She was going to go into a dangerous spiral if she started imagining Holtz' abs. She wondered how Holtzmann had gotten so fit. She'd throw 100lbs of ghostbusting equipment over her shoulder like it was made of Styrofoam. Erin could barely even lift her proton pack some days.

"How are you so muscular?" Erin blurted. In addition to being a bumbling idiot, she also lost any sort of filter when she was in the presence of an attractive human.

Holtz spun in her swivel stool to face Erin without breaking from her position. She raised an eyebrow at underneath her goggles. Then she dropped her hands, moved into a more natural seated position, and started pulling herself around the table, all while maintaining eye contact. When she reached the edge closest to Erin, she spun so she was facing the table. Then she bent her knees, propping her feet against the table, and kicked off, send the stool (and her) zooming backwards across the room towards Erin.

"You're going to hurt—" Erin started to say, but then she broke off as Holtzmann, attempting to spin as she was rolling, underestimated the momentum and gravitational pull, and flew off the stool. She landed with a crash on the concrete floor. "—yourself," Erin finished. She rushed over to where Holtz was curled up on the floor.

"That was gloriously stupid," said Holtzmann. "Can I go again?"

Erin helped her sit up, and then a deep frown flashed across Holtz' face and her hand flew to her upper chest.

"Are you okay?" Erin asked.

Holtz didn't answer, but she started pulling off her oversized jacket. Erin moved to help her. Well, this wasn't how she had imagined taking off Holtz' clothes. Underneath she was wearing a crop top and overalls combo, which Erin recognized immediately as the outfit she had been wearing on the day they met. Holtzmann had introduced herself with a pick-up line, and Erin had been falling for her ever since.

Holtz shrugged the straps of her grease-covered overalls off her shoulders, wincing a little, and then her crop top was showing a lot more skin than the little strips along her side that Erin usually stared too long at whenever Holtz wore this outfit. Even though this was a dire situation, Erin couldn't help but peek at the strip of stomach now visible. Oh, yeah, she was right about the abs. Was she ever right.

"What Holtz? I mean…what hurts?" Erin said.

"Take off my necklace," replied Holtz, in a throaty voice that made Erin curl her toes in her boots. Then she cleared her throat. "Wait, that was weird. Apologies. I'm used to saying that phrase in slightly more…sensual contexts."

Erin nearly choked. This feels pretty darn sensual to me, she thought as she unclipped Holtz' signature jewelry piece. She went to hand it to Holtzmann, who shook her head.

"Keep it safe. I don't want anyone in the emergency room cutting it off or nabbing it. That necklace is an essential part of my personality."

"Wait—emergency room?"

Holtzmann smirked. "Oh, yeah. My collarbone is definitely broken."

Erin gaped down at Holtz. Her smirk started to fade when Erin hadn't said anything after several seconds.

"What, no freak-out? Did I finally send you into shock? Success. I would be pumping my arm in the air right now, but collarbone."

That snapped Erin out of it. "Oh my God, Holtz. Okay. Okay. Crap. Okay. I'm calling an ambulance."

"Nah, let's just take the hearse. It's classier."

"We're not driving a hearse to a hospital."

"We're not, but you are."

Realizing that Holtzmann wasn't going to budge on the issue, Erin sighed in resignation and gently helped her to her feet. Together they walked down the stairs (Holtz only made one comment about going down the pole) and to the garage. Erin made sure she got Holtz settled before she went around and slid into the driver's seat.

"I don't dare put my seatbelt across my chest right now, so keep that in mind as you drive, Gilbert."

"My driving is way safer than yours will ever be," replied Erin as she pulled out of the garage, sirens already blaring. "Also, how can you still be so sarcastic with a broken collarbone? Aren't you in pain?"

"Ooooh yes." Holtz grinned, and for not the first time, Erin was more than a little concerned about her sanity. "Drive a little faster, won't you? The sirens are made for clearing traffic. You just can't be afraid to weasel in where there's enough space. And sometimes, even where there isn't."

"Sound advice," Erin mumbled, hitting the accelerator.

Once they had arrived at the emergency room, Holtzmann slumped back into one of the waiting room chairs in typical Holtz fashion, except with her arms crossed instead of behind her head. Erin went and got the paperwork from the front desk, and was told that it was going to be a long wait because a broken collarbone wasn't serious. Erin almost yelled at the lady, because Holtzmann was in pain and how dare nobody seem concerned? She stalked back over in a huff to where Holtz was seated and plunked down in the seat next to her.

"Want me to fill this out for you so you don't have to move your arm?" Erin asked.

"That would be grand."

Erin clicked the pen and stared down at the form, suddenly aware of how little she knew about Holtzmann. She didn't even know her birthday, for crying out loud. Holtz seemed to realize this at the same time, and she started supplying the information without Erin asking. By the end of the form, she knew not only Holtz' birthday (which she was reluctant to give out, possibly because it was in less than a month), but also her middle name (which Holtzmann made Erin swear she'd never repeat to anyone ever). Erin finally finished the form, and then she sighed.

"I hoped that would take more time. It's still going to be a long wait, it seems."

"Didya tell her I was a Ghostbuster?"

"No…that's smart!" Erin went to stand up but Holtzmann caught her arm and pulled her back down.

"I was kidding. It's never worked before."

Holtz held onto her arm for several seconds longer than was necessary, and Erin's next words stumbled out of her mouth as she took in that information. "I forgot that this isn't a first time occurrence for you. What was it last time, again?"

"Burn," Holtzmann replied vaguely. Erin always seemed to be gone when Holtz injured herself, which was probably for the best. This was killing her, watching Holtz suffer. This was why she always got so angry when the kooky scientist was reckless. Erin always told herself it was in the interest of the practice that she got so upset, but she knew the truth was that she didn't think she'd ever get over it if something bad happened to Holtz.

Holtzmann let go of her arm, then, and Erin took the opportunity to go take the form up to the front desk so Holtz wouldn't see her hyperventilating. She took a few deep, steadying breaths at the counter before turning back around. Back at their seats, Holtz' eyes were closed, and Erin wondered if she was falling asleep. She looked so innocent, surrounded by the bustle of the emergency room. Calm. Vulnerable. Erin swallowed a lump in her throat as she walked back over and took her seat again. Holtzmann didn't say anything, and remained still, so Erin thought maybe she was asleep until a few seconds later, when Holtz gently but purposefully dropped her head and nestled it into Erin's shoulder.

For a few seconds, all she could register was a mix of panic and joy, topped off with the steady internal screaming that was occurring in her head. Seconds turned into minutes and Holtz didn't move. Erin slowly relaxed, calmed by the gentle rhythm of Holtzmann's breath and all the scents that she had never noticed before. She had only ever smelled the motor oil that wafted off with every step Holtz took, but at this close proximity, she could also smell plain soap (did Holtzmann wash her hair with hand soap?) and a deep musky, spicy scent, which Erin guessed might be some sort of cologne. It smelt like…a lumberjack baking gingersnaps. It was assertive and robust, but sweet, and it was so perfect for Holtzmann that Erin felt herself getting choked up. Oh my God, was she losing it over the way this woman smelt? She was in a lot deeper than she thought.

Erin was so content that she almost got angry when, a few hours later, a tired looking man with a clipboard called Jillian Holtzmann?

She was so unused to hearing Holtzmann's full name. She went to nudge Holtz, assuming she was for sure asleep if she could stay motionless on Erin's shoulder for hours, but she was already moving her head and standing up.

"I'm going to be stiff tomorrow," said Holtz, stretching her neck from side to side and smirking at Erin. Then, so quiet Erin wasn't sure if she was imagining it or not, she added: "Worth it." Then she was walking away before Erin could react, and the last thing she could hear before she was out of earshot was the scientist say to the clipboard man: "That's Doctor Holtzmann to you, good sir."

Yeah, Holtzmann was definitely going to be Erin's cause of death.