It happens because they just finished sparring, and they're tired and sore and hungry, and neither of them is thinking—which is rare enough that neither of them realize it, either.
They're discussing the spar—Shikako calls it arguing, but that's undignified, and anyway Sasuke won so there's nothing to argue about—while they walk down the street. Shikako healed them both after the fight, but the right part of her sleeve is hanging by a thread after being singed by Sasuke's Grand Fireball, and he still smells like smoke from getting caught at the edge of one of her Touch-Blast seals. That's the thing about fights with Shikako: she gives as good as she gets, and the outcome is never predictable. He knows more jutsu, but she's faster, and she relies on skill and strategy and seals, none of which he can copy. Sure, he won this time, but there was a fair bit of luck involved.
Luck, and a new Raiton she hadn't been expecting.
"...but I'm just saying, if I'd used the Replacement Jutsu after you broke out your ninja wire-" Shikako stops. "Oh."
Sasuke follows her gaze, and suddenly realizes that they've been surrounded by the smell of broth for a while now.
They're both silent. Then, as if on cue, their stomachs rumble, and they glance at each other.
Shikako politely ignores Sasuke's flush—he can feel it climbing up his neck—and tilts her head. Should we...?
Sasuke considers, a little annoyed by his own hesitation—there's no real reason not to, after all. It's not that ramen is bad, per se, it's just that it's really salty and there are other foods... But he nods once, and ducks under the flaps. He can hear Shikako do the same.
"Ah, Shikako-chan, Sasuke-kun, welcome!" Teuchi beams at them both. "It's been a while, hasn't it? How have you been?"
"Well, thank you, Teuchi-san," Shikako says, sliding into the seat at the end of the counter. Sasuke sits down next to her. "Um...can I get a regular shoyu ramen, please?"
"Of course. And a regular salt ramen with extra tonkotsu for you, Sasuke-kun?"
"Thank you," Sasuke says politely. He doesn't miss the way the chef's eyes flicker up and away from him expectantly, and the way the older man's expression falls afterward, when he remembers.
They make small talk with the man as he putters away: he comments on their chunin vests (and gives his congratulations); Shikako regales him with some of the flashier battles (he oohs and aahs appropriately); he tells them about his business (it's thriving); Shikako asks after his daughter (apparently she's apprenticing at a dango shop a few streets down).
Alright, so it's mostly Shikako who talks, but Sasuke does comment occasionally. He may not have much patience for small talk, but he's not rude, either.
"Here," Teuchi finally says, as he sets the steaming bowls down in front of them. "Half off today, in celebration of your promotion! Congratulations, both of you!"
Sasuke glances at Shikako and is gratified to see that she looks just as startled as he feels; their promotion was a while ago. "Ah, thank you, Teuchi-san, but there's really no need—"
The chef waves her words away. "No, no, I insist! It's a small thing—you're Naruto's teammates, after all!"
Then another customer walks in, and Teuchi turns to greet them.
It takes them a bit longer than usual, but Sasuke and Shikako eventually ease back into normal conversation. There's not much she can tell him about her work in Intelligence, but she's good at glossing over the classified parts and jumping into the details of her weird coworkers, from Ibiki to Anko to even Ino (who he's been gaining a grudging respect for, these days). He talks about training and his mission runs with the border patrol, not missing the gleam in her eyes that betrays how much she misses being out in the field. She tries to wheedle him into testing a new seal she's been working on, and though he refuses at first, he can't deny that a part of him is curious to see if it works as well as she claims it does.
And through it all, they are careful not to pay attention to the empty seat on Sasuke's right, or the silences when they're both eating that would normally be punctuated by loud exclamations or outlandish stories.
It's not the same, with just the two of them.
Finally, they finish their ramen. "Gochisousamadeshita," they both say, leaving their money on the counter and scooting their chairs back. That was delicious. They duck out with Teuchi's "Please come again!" ringing in their ears, and the taste of salty broth in their mouths.
On the walk back, they lock eyes, and silently agree not to go back to Ichiraku's again.
Not until he comes back.
A/N: It's called fanfiction for a reason, so don't crucify me if they go eat at Ichiraku's in SQ's next update ;)