**Note: Riku uses the word "accelerate" in the scientific sense, as in, a change of speed, be it an increase or decrease.**

Part Four

Numbers were easy, for Riku. Those weren't the problem. It was calculating the time until his date—meet-up, he amended—with Sora that was the problem. Time marched forward in uniform velocity, though sometimes he swore it accelerated—sometimes faster, sometimes slower—and his mind tried to formulate derivatives so that he could calculate the time more accurately.

Which, of course, was silly. Time didn't accelerate.

He tried instead to focus on the simpler equations he laid out for his students. If he didn't, he would probably find himself caught between being excited and being terrified about the upcoming weekend.

He supposed he could probably calculate the gravity between him and Sora, too, but that would be entirely fruitless, and anyway, he hadn't studied enough Physics for that. If that even fell under the realm of Physics.

And it wasn't a date.

Sora greeted him throughout the week. In the halls and the parking lot and the lunch room, and sometimes they got a few words in. Sora stopped by Riku's classroom to say good bye in the afternoons, and that made Riku a little dizzy, that he would seek Riku out.

Friday, Sora poked his head in the classroom with his usual smile. "It's the weekend, so don't stay too late!"

Riku glanced up from his work, unsure how to respond. Weekends weren't really special. Except this weekend was; he fiddled with his pen. "I'll try not to."

Sora stayed just inside the door. "Don't forget about tomorrow! You know, maybe you should pick the place, since I'm still getting used to the area."

"Oh. Right." Well. That was great. Riku wondered if Sora was expecting them to go to a bar, or if he'd be satisfied with something more low-key.

Sora crossed his arms, looking a little smug. "If I don't hear from you tomorrow, you won't hear the end of it!"

Riku let out a something like a small laugh. "I won't forget."

Sora beamed. "Good!" He gave a salute and departed with a, "See you then!"

Riku waited until Sora was clear of the room before pulling his phone out to text Namine. She would know better than him where he could take Sora.

O.o.O

It wasn't a date.

Riku had reminded himself of this uncountable times, and still he found himself agonizing over his appearance. Did he pull his hair into its usual bun, or a more relaxed ponytail? Or leave it down, for a change? He was sure if he left it down he would spend the whole night pushing it behind his ear, but on the other hand, he could hide behind his fringe. Did he stick with his usual button-up, like at work, or go for something more casual? He'd only ever seen Sora wearing t-shirts and athletic shorts and pants, but would he dress up for their outing?

He decided on a compromise: a button-up, with jeans, instead of slacks. He'd be lying if he denied that he was wearing the jeans because they were more form-fitting than the slacks. His hair he left alone, and he reminded himself not to play with it too much.

He'd already texted Sora with the place that Namine had recommended. It was a local bar and grill, with a partition between the bar and the dining area. Riku wondered what the convention was, for this. Drink at the bar? Have dinner, too? He spotted Sora's messy hair, already at the bar, though, and let out a sigh of relief that he didn't have to make that decision.

"Popcorn?" Sora asked, offering Riku the bowl of it once Riku had taken a seat. Riku glanced at the glass already in front of Sora: it was still mostly full.

"Ah, thanks. Did you just get here?"

Sora nodded. "Just long enough to get my drink. I would've ordered for you, but I didn't know what you'd like." Riku's breath caught, and he was glad that Sora had turned his attention to waving down the bartender.

Riku immediately chided himself. Sora was just being courteous. Riku ordered his drink, and let out a self-deprecating laugh. "It's been a while since I had anything stronger than espresso," he admitted, once it was placed in front of him.

Sora chuckled. "So, you're probably due for one, right?"

Riku felt his lips turn up in a strained smile. "Yeah, I suppose so."

He'd only just wrapped his hand around the glass when Sora remarked, "I think this is the first time I've seen your hair down. I didn't realize it was so long."

"Uh." Riku abandoned his glass in favor of pushing his hair behind an ear, and then grimaced. That was exactly what he'd wanted to avoid. Anyway, Riku was used to hearing such comments. It was not like Sora had complimented him, really. "It's easier to manage. For school."

Sora grinned and ran hand through his own hair. "I can't even imagine having hair that long. It suits you, though."

"T-thank you." Riku gripped his glass, and took a long draw from it. He savored the warmth traveling down his throat to his stomach, and finally allowed himself to look at Sora. He, too, had gone with jeans—Riku mourned the shapely calves that were now hidden beneath the fabric—and paired it with a t-shirt with aesthetically pleasing graphics. It was, compared to his normal clothing, dressed up.

Riku tried not to read into that.

Sora was a fun companion, Riku decided, halfway through their second round of drinks. His complaints about the school and the students were good-natured, with room for Riku to chip in with his own experiences. He'd launched into a story from college when they ordered a third round, and Riku found himself admiring the way his blue eyes sparkled, and the lively gestures that accompanied the story.

And that smile. God, this had been a bad idea, because if Riku had been infatuated with Sora's smile before, he'd now fallen in love with it. Actually, he thought, he was in love with Sora's mouth in general, and wanted to know how his lips would feel against Riku's own, and if he'd be able to taste the flavor of Sora's drink past the taste of alcohol in his own mouth.

It had, as Riku said, been a long while since he'd had a drink, and he was a lightweight to begin with. He'd thought to stop after the second drink, but he was feeling good, and it was nice to enjoy Sora's company. And anyway, he was already feeling more confident in himself.

"Hey, Sora," he said suddenly, "are you seeing anyone, right now?"

Sora's brow furrowed, and that was a cute look. "Nah. It's been a bit hectic, with graduating and starting work here, you know? I didn't know where I was going to find work, and I didn't want to make someone else have to rearrange their life around mine."

"Good, that's good." Riku knew he was smiling as he settled his elbow on the bar, leaning towards Sora. "You know, you kind of remind me of the square root of two."

Sora blinked. "Oh yeah? Why? You know, I told you I'm not great at math—"

Riku's smile stretched into a grin. "Because I feel irrational around you."

Sora broke into a laugh—a giggle?—and tilted his head towards Riku conspiratorially. "You sure it's not the alcohol?"

"I'm sure it's not." He propped his chin on his hand to look at Sora. If his head felt a little light, maybe that was from the alcohol. Maybe it was from the person in front of him. Probably a little of both. "They're tangential to each other," Riku murmured, "the alcohol and being around you, taking me in the same direction." Yeah, he was definitely irrational. He felt warm and languid, and full of possibilities, and Sora's lips were so close.

So inviting.

Sora's cheeks were pink, and maybe that was the alcohol, too. His smile was lopsided. "You're just teasing me, with all that math stuff." His blue eyes were bright.

Riku's mind was fuzzy, everything bright, but he knew he wasn't teasing. "I'm not." He had to slide off the bar stool to close the distance between them. Forward momentum, and gravity, and all of that, and he pressed his lips to Sora's, sliding his hand to cup Sora's cheek. He had to bend a little to do it, even with Sora sitting on the bar stool, and he liked that, and he liked the way Sora's lips were pliant against his own.

But—

Sora had a hand on his chest, pushing him gently away. Blue eyes wide. "Riku…" The chiding tone sent Riku's stomach plummeting. His cheeks were hot and it wasn't from the alcohol, in fact, he felt sober, suddenly. He took a step back, giving Sora the space that the hand on his chest demanded.

"I—" He was mortified. He tried again. "Sora, I—"

He couldn't read the expression on Sora's face. "I think maybe you drank a little too much."

Riku felt his breath catch in his throat. Sora wasn't wrong. Riku pressed a hand over his eyes. "Yeah. Yeah, you're right." He drew his hand down to pinch the bridge of his nose. "I'm sorry." He couldn't bring himself to look up at Sora, and instead fished his wallet out of his pocket. He counted out some cash—enough to cover the tab for both of them—and set it on the bar, before spinning on his heel.

He hadn't made a step before Sora's hand closed around his wrist, warm. "You shouldn't drive."

Riku didn't turn. "I won't." He pulled away, and Sora let him.

The distance between the bar and the door was short, indistinct and oppressive in the face of what he'd just done, but it was a point of pride that he didn't stumble, despite how unbalanced he felt.

Outside, it was cooler, the air almost crisp with a hint of fall, and he gulped in deep breaths of it.

He'd done it. He'd ruined it, before it had even begun. Sora would never smile at him again, not even in the capacity of a friend, and the best that Riku could hope for, now, was that no one else would find out about his gaffe.

He let his hands fall limp at his sides, and took a deep breath. Riku turned his feet towards his apartment and started walking. He would get his car in the morning. Walking was better. It cleared his head, and sobered him, and the activity tired him, physically, so that when he made it to his door, and then his bed, he was able to collapse and fall asleep.

He didn't want to ever wake up.

But he did, and it was to the sound of his phone ringing. He fumbled for it—the name was blurry, and he groped for his glasses, only to let the phone fall to the bed when he saw Sora's name across the screen.

Of course. Sora was a nice guy. He'd check to make sure Riku had made it home. With a groan, Riku turned over, ignoring it. He could try to pretend the night before had ever happened, but he knew it was impossible. Sora would see him alive and well the next day at the school, and then he'd be satisfied, and they wouldn't have to talk again. It would be life as it had been, before he had even met Sora.

He thought again of Sora's smile, and hugged his comforter tighter over his shoulders.