Rachel Ellis had discovered there were two kinds of rules.

  The first kind were the ones you broke once, felt vaguely rebellious about, and then forgot existed.

  The second kind were the ones you broke once and immediately understood had been installed for public safety.

  Their Sunday-and-Wednesday rule was firmly the second kind.

  It existed for the same reason lab safety manuals existed. Not because you expected disaster every time, but because you only needed one truly stupid mistake to learn humility forever.

  They’d come home from the train on Sunday with their hands still linked and their voices still full of the words they’d said in that house. There had been no hesitation. No noble attempt at restraint. “I love you” had entered the relationship like a new highly volatile chemical reagent—one that didn’t look dramatic until you added it to the mixture and suddenly nothing behaved the same way again.

  Monday morning had proven, immediately, why Sunday nights were banned.

  They’d been late. Not “miss the first half of class” late, but late enough that Rachel had walked into the chemistry building with her hair pinned up too fast and a humiliating awareness that she looked exactly like a woman who was recklessly, dangerously happy. Noah had sat at his bench and looked at her like he was still tasting the word love. Rachel had barely managed to teach, clinging to glassware and safety protocols like a religion.

  By Tuesday morning, they had fully abandoned survival instincts.

  Because Tuesday morning wasn't a rule day. They’d intended to be responsible. They’d intended to have coffee and eat breakfast at home like normal adults. Instead, Rachel had looked at Noah in the pale early light, sleepy and unguarded and looking for coffee filters, and her brain had offered exactly one coherent thought:

  Mine.

  The next fifteen minutes had been… educational.

  They’d left the apartment with damp hair, zero caffeine, and the kind of hurried affection that had directly led to Rachel’s near-implosion at the campus café an hour later. She was still blushing over the fact that she had almost called to him casually and sweetly in front of God and a barista, entirely distracted by the terrifying new normalcy of being in love.

  Now—Tuesday afternoon—Rachel sat at her desk with a stack of lab notes in front of her and exactly zero ability to focus.

  She opened her laptop to check her email, only to be immediately assaulted by a digital calendar alert she had set three weeks ago.

  Friday, Oct 30: Noah's Birthday.

  Rachel stared at the screen. Her blood ran cold.

  Three days. She had exactly three days.

  Before this weekend, buying Noah a gift would have been a matter of finding something pleasantly thoughtful—he had mentioned something about wanting to try a French press at some point, a couple weeks prior. She would’ve gotten him something that said, I enjoy our time together and I pay attention to your morning routine and we’re progressing at a normal, socially acceptable velocity.

  Now, they had fundamentally shattered the pace. He had stood in his family’s home and offered her his entire heart, and now she had to buy him a present that lived up to that.

  A French press felt almost insultingly practical now. It was a Tuesday-morning gift. It wasn't an I-love-you-and-I'm-terrified-but-I'm-jumping-anyway gift.

  She leaned back in her chair, tapping her pen against her desk. What do you buy a hyper-organized STEM major who alphabetized his pantry, actively avoided celebrating himself, and already possessed an aggressive amount of office and kitchen supplies?

  The narrative has been illicitly obtained; should you discover it on Amazon, report the violation.

  She thought about his apartment. The clean lines. The tidy desk. The single, slightly chaotic element was the small stack of vintage paperbacks he kept on his nightstand. Sci-fi.

  Forty-five minutes later, Rachel pushed open the door to a sprawling, slightly damp-smelling vintage bookstore a few blocks off campus. It was the kind of place where the organization system was essentially "vibes" and the shelves looked like they might collapse if you looked at them too hard.

  It was a nightmare for Noah's sensibilities, though it was undoubtedly the perfect place to find a hidden gem.

  Rachel navigated to the Science Fiction section, sliding her fingers over cracked spines and faded dust jackets. She smiled, remembering the first time he'd let his guard down about the books. Noah usually measured his words with the exact, careful precision he used in the lab, but when he talked about old-school science fiction, something shifted. A giddy, almost childish energy would break through his careful exterior. He would talk faster, his hands moving to emphasize a point, his eyes lighting up as he explained faster-than-light travel paradigms or theoretical terraforming ethics.

  Rachel rarely understood more than half the actual physics he was referencing, but it didn't matter in the slightest. She could listen to him talk like that all day, just to watch his face do that.

  She picked up a copy of Dune. No, the spine was broken in three places. Noah was particular about his books, and this one had been loved to death by someone else.

  She found a collection of Isaac Asimov short stories. It also didn't fit the bill. He'd quoted one of these to her during that terrible robot apocalypse movie they'd watched three weeks ago, taking a deeply pedantic and entirely endearing issue with the film’s misinterpretation of Asimov's Three Laws of Robotics. He already owned it, and it was probably alphabetized already, too.

  Rachel stood in the narrow aisle, entirely surrounded by the smell of old paper, and realized exactly how well she knew him now. She knew what would make his eye twitch. She knew what would make him smile that slow, devastating smile. She knew he didn't need anything practical, because he provided all his own practicality. He needed something that he didn’t know he wanted.

  Her eyes caught on a dark blue spine tucked on the top shelf.

  She pulled it down. It was a beautiful, remarkably pristine 1970s hardcover edition of Ursula K. Le Guin's The Dispossessed. Noah had mentioned it once, completely offhand, noting it was the book that had originally made him interested in the physics of time and communication.

  She traced the cover. It was perfect. It was logical, it was beautifully preserved, and it was deeply sentimental without screaming it. It was exactly the kind of quiet, steady thing Noah was, wrapped up in a slightly worn dust jacket.

  Rachel took it to the front counter, sliding it toward the cashier with a feeling of profound, triumphant relief.

  "Good find," the older man at the register noted, inspecting the spine as he carefully rang it up. "Don't see this edition in this kind of shape very often. It's a classic."

  "It is," Rachel agreed, unable to keep the sudden, bright warmth out of her voice. "It's a birthday gift."

  The man chuckled, sliding the book into a paper sleeve. "Well, he's a lucky guy."

  Rachel thanked him, carefully tucking the wrapped book into her tote bag like she was transporting a highly fragile isotope.

  Stepping back out into the crisp autumn air, the low-level panic that had been humming in her chest since the calendar alert finally dissipated. The sun was getting low, casting long, golden shadows across the pavement, and the wind had that sharp, clean bite that smelled like dry leaves and impending winter.

  For the first time all day, her heart rate actually settled into something resembling a normal rhythm. She had the gift. She had survived the day. And she was going home.

  As their apartment building came into sight, she pulled out her phone, her thumb hovering over his name.

  Rachel: When will you be home?

  The typing bubble appeared almost instantly.

  Noah: Just wrapping up now. Is there a logistical emergency?

  Rachel smiled, the crisp air suddenly feeling a lot warmer. She stopped at the edge of the crosswalk, typing with both thumbs.

  Rachel: No logistics. I just miss you.

  Noah: It has been exactly four hours and twelve minutes since I saw you.

  Rachel bit her lip, a ridiculous, irrepressible flutter starting up in her ribcage.

  Rachel: I know. ETA?

  Noah: If I leave now, I can be there in fifteen. If I run, twelve.

  Noah: And, for the record, I miss you too.

  Rachel: Don't run. But don't walk slowly, either.

  Noah: See you in thirteen.

  Rachel slipped her phone into her pocket, clutching the strap of her tote bag as she started the walk back to her apartment. The heavy weight of the book against her hip felt like an anchor, grounding the dizzying, free-fall sensation that had been spinning inside her since Sunday.

  The Sunday-and-Wednesday rule was absolutely necessary. It kept her employed. It preserved whatever shred of academic dignity they still possessed.

  But Tuesdays were blessedly uninhibited by rules, and were a reminder that, outside of those two carefully protected mornings, Rachel was free to let herself be exactly as reckless as she wanted. She was allowed to feel this giddy, incessant flutter. She was allowed to count down the minutes until thirteen of them had passed.