i: ⇄

It does not surprise Manami that, two hours after graduation, she finds herself standing at the bottom of the stone steps that lead up to class 3-E, brought about by wondering and wandering down memory lane.

Manami climbs up, up towards her second home, wandering the corridors towards the laboratory, fondly running her fingers on wooden walls that whispered of belonging. Manami slides open the door, soft eyes adoring as they survey the cupboards, the tables, the diagrams. Spotless beakers and flasks and cylinders. The rickety floorboards, the wizened walls, the blackboard with leftover scratches of chalk. Manami inhaled deeply, completely at ease, stretching her arms above her head and smiling.

This is how Karma catches her; a hand latches around her waist and his knife at her throat. Manami lowers her hands to look at him, surprised and amused at the same time.

She smiles. "Hi Karma-kun."

"What's this, it's only Okuda-san after all!" he chuckles. "And here I thought someone was trying to break into the building."

Beneath his smile, there's a glimpse of something sad, something that longs, and something she doesn't understand. Karma lets her go, but then grabs her hand, twirling her about like an impromptu dance. He tilts his head to the side, head angled down for her. His eyes are guarded again.

"Though, what exactly are you doing here in the first place?"

"One last look at class 3-E's lab." Manami glanced back at the room with fond eyes. "In high school, the lab would probably be bigger, probably better, but this lab will always be my favorite."

"Really, now?" His eyes sparkled. "So, how about one last business transaction? Some cyanide in exchange for something you want?"

Manami laced her hands together behind her and played along. "And what will you do with that item this time?" Karma pretends to think, tilting his head further, eyes averted and narrowed in mocking thoughtfulness. This, too, Manami thinks. She'll miss it, too. It dawns on her that without Karma, mischief incarnate Akabane Karma, high school life would be quite boring, and she'd wondered about that often.

High school, compared to their illustrious junior high school life, would be one awfully ordinary affair.

Karma's hand is on the crown of her bowed head. "I'll miss everyone too," he says with a shrug. "But mostly the fun parts of it."

"Fun for you is usually dangerous for anyone involved." He gasped at this, grasping his chest as he pouted.

"I'm offended!"

Manami giggled, "What about you, Karma-kun? Why are you here?" She squeezed her fingers together as his grin softened to an easy smile. A thought struck her, and she added, teasingly: "Did you follow me?"

His smile was cheeky. "No," but then adds, "but maybe I was wondering what Okuda-san was doing by coming back up here, so, being the good friend I am, I wanted to make sure that you're safe! No need to thank me… though the cyanide would do just fine."

Manami pursed her lips to a smile.

"Alright." Karma looks too entirely pleased, but Manami just pulls him inside the lab anyway. "But I think you're just lonely."

"So which school will you be in?"

Karma fiddles with a bottle of ammonia, throws it in the air twice before Manami takes it from him, a stern look thrown at him that he merely smirks at. Only then does she process his question, and she raises both eyebrows at him. Karma grins widely, innocently, and Manami debates if she should believe it as she raises the mask over her nose again.

"You're not thinking about following me there too, are you?"

He flicks her forehead. "Maybe… but who knows?"

Manami hadn't really thought about the possibility of seeing and having anyone as classmates again when they graduate. But, their legs bump, and he raises his hand to her shoulder, picking at an imaginary lint, it wouldn't hurt to have a familiar face close by too.

"Well… I'm going to Oku Tokyo." She grins when the boiling slowed, the fumes giving her a rush of pride and odd elation; something Karma notices, and there is fondness in the way he looks at her that she doesn't notice. "Well, I mean, until I receive my entrance exam results from Seikei, Oku Tokyo is my first choice."

He cushioned his chin on a fist. "You should go for Oku Tokyo regardless if you passed Seikei."

"Why is that?" She shut off the burner excitedly, the mask unable to hide how the corner of her eyes crinkled with happiness. "It's done!"

Karma leaned forward to inspect the mixture, putting his hands up when she swatted him away to keep his distance.

"It's nearer, which makes it practical," he shrugged. "You'll need two trains to travel to Seikei every day, coming from here, and that's a lot of hassle. It's either you commute, or stay in a dormitory. And I hear dorm life isn't fun at all."

Manami frowns contemplatively. "Well… I already live in an apartment with my parents, so a dormitory doesn't sound like a good idea… but that's not a very convincing reason why I shouldn't go to Seikei."

"Practicality is enough reason to attend Oku Tokyo. It's near, and it's a great school with a great science curriculum. It's definitely your school, Okuda-san, just saying."

"Is it?" She lowered her mask and beamed. He followed her actions just a second later, and Karma tugged on one braid, so that her eyes returned to him. "Maybe I'd study at Oku Tokyo after all."

"You're gonna be kick-ass in that school, I just know it." And then, Karma laughed devilishly. "If Koyama happens to be there too, you better own him good!"

"Of course!" Her glasses glinted. "Science is my subject, Karma-kun."

"Yours? Like a lover?" he mourned. "Looks like I failed in protecting you, for a suitor managed to get past me after all…"

Manami bites back a laugh, grabbing his hands in hers as she held the bottle.

"Science may be my lover, but Karma-kun is my favorite partner in crime." His fingers closed around the bottle of cyanide, over hers. It's funny how they hold something dangerous in such a way. She isn't sure if it's because of his hair, or the setting sun, but there is a rosy hue to his cheeks. Manami refrains from mentioning it, but she can't help the heat on her face as he looked her in the eye, nonetheless. She holds onto what pieces of courage she had, tightens her fingers around his. "And I'll… I'll miss you, too."

Karma grins widely, cooing, "If you continue saying things like that, I might just follow you after all."

Karma, she learns the same day, lived the opposite way. This does not stop him from walking her home—at least, towards the train station.

She would say that she minded, since he lived the other way and that there was no reason to accompany her, but it was nice, having his company even as it seemed like the last. The sun has set, and the air is sweet with spring blossoms. The train station is crowded, but manageable, and they easily slip through the crowd so that they were one of the people in front.

"The next train's coming in 20 minutes," she observed, smiling up at him. "Thank you for walking me here, but are you sure it's—"

"Okuda-san," he waved her off, and Manami huffed. "I wanted to walk you here. No one's bothering anyone, no harm done."

"You're also going to wait here with me until the train arrives, aren't you?"

When he answered her with a wide smile, Manami concedes with an amused sigh as she stood closer to him, mindful of the growing crowd around her that also waited for the next train. A hand brushed against her thigh, a little too close for comfort, and she was pressed to Karma's side before she could even react.

"Watch it," he hissed, his grin too sharp to be friendly, poised to another male student in a different uniform. The student recoiled with a frightened apology as he bolted far away from them. Manami could only look at his retreat with a nervous smile, and raised an eyebrow towards her companion. He held her tightly around the shoulders, eyes following the retreating student and she nudged him on the stomach so he's looking at her again.

"I'm entirely sure that was an accident."

"I'm entirely sure that it wasn't," he scoffed. "Accident or not, no one touches Okuda-san inappropriately."

Manami tries to pretend she doesn't feel flattered, reasons that he is merely looking out for her like he always does. "T-That's sweet."

A minute passes, each second ticked by station chatter and the announcements through the speakers. Manami observes, listens. It's difficult to focus when your heart is beating a little too fast, so Manami tries to fix that, and succeeds to fail in that. It's not uncomfortable, but it's not something she was used to, either. But it was a nice feeling, and Manami liked it. Pressed as close as she was, Manami could smell the fresh, clean scent of his clothes.

"You haven't asked me which school I'm in." He suddenly says. "Wouldn't you want to know?"

Manami perks up. "Well, where are you going?"

So he tells her then that he was staying at Kunugigaoka, that he had loose ends to settle with Asano and that it'll be a much fun ride because in high school, there is no class 3-E to look down on, no strings to pull but academics and credits and extracurricular activities, and that he was looking forward in competing with him in all aspects. If junior high school had been difficult (she remembered those grueling lessons, the humiliation they would endure with every assembly, the less-than stellar grades, Korosensei and this, this, is how the ache in her chest deepens), she could only imagine how hard high school would be.

And with its aces in a constant academic war, she hoped Kunugigaoka would do its best.

"You can do it," Manami smiles encouragingly, squeezing his side in a loose hug, and he grinned appreciatively at her. "Karma-kun and Asano-san may be equals, but I've always believed in Karma-kun."

"You're gonna be great too, you know." He winked. "Wreak entropy for me?"

Train tolling.

Despite herself, Manami laughed, and Karma held her tighter. "T-That was a weak joke!"

Engines whirring. Rail tracks screeching.

"But Okuda-san laughed!"

Manami smiled, closing her eyes. "I guess I did." In less than three minutes, the train would arrive, and Manami focused on its approach. She'd felt him sigh, and then he's ruffling her hair, messing up her braids.

"Karma-kun!" He's laughing again.

"I forgot to tell you that I have another reason." Then train comes whooshing to a stop in front of them, her messy hair agitated and helpless to the sudden movements and almost drowning out the sound of his voice. "Won't you ask me what it is?"

The chatter and noise had escalated to new levels. People pushing, coming in and out of the train. Warnings to stand before the yellow line, periodic. Reminders that the doors are closing in one minute, incessant. The pounding in her chest, baffling.

"What's your other reason?" The noise had her raising her voice just so he could hear her.

Karma presses something in her hand—small and circular. She can't see it yet, but she holds onto it tightly.

"It's one train ride away!" he shouts with a grin, then he's pushing her into the cab just in time before the doors shut close. He stands on the other side of the doors, mischief incarnate with his signature sharp grin and Manami could only stare back, confused. The train moves, gains speed, and Manami sees that he doesn't move until he couldn't see her anymore.

Manami didn't understand his words. In fact, she didn't understand Karma at all today. One train ride away...?

She opened her hand carefully against the sway of the other passengers, feeling less rattled and more breathless, blinking at what she saw.

What was his purpose by giving her this?

When Manami got home, she checked all of her jackets, counting all buttons twice. All of them were firmly stitched and not one button was missing.

He'd given her a button, but Manami didn't know what to do with it.

outside the windows of our classroom is also found on ao3 under chuunihans for the series, one train ride away.