Word Count: 1,079

Armin walked into his English class one Friday morning to find a small, triangularly-folded note sitting in stark contrast to his brown wooden desk. Curious, he picked it up and flipped it over, expecting to find something– he wasn't sure what (maybe a name or something?)– on the back to cue him in as to its origin or purpose.

There was absolutely nothing.

For a moment, he considered tossing it, or asking his teacher, Ms. Nanaba, about it, as if she would know anything. But his curiosity got the best of him and he very carefully unfolded the note.

Before it was even all the way open, he saw numbers printed very neatly in the upper third of the paper; they had been cleverly hidden in the folds. It was not a code he was familiar with, so he finished unfolding it, and, finding nothing but numbers on the first side he saw, he flipped it over.

It was sheet music. Probably meaningless.

He flipped it over to the side with the numbers on it again.

54 115 92. 16 20 23 98 32 80 / 1 92 7 22 / 22 8 / 9 49 60 / 42 54?

They had no pattern whatsoever that he could see, and he was very good at looking into things and finding patterns in them. Perhaps the sheet music on the back had meaning after all…

He flipped it over a third time and tried to play the melody in his head. After a few seconds of struggling, its motifs began to become familiar as he got better at sight reading the rhythm and notes. Realization hit him like a pile of bricks: it was the Can-Can.

The same instant as the full piece began blasting in his head, words came as well: This is the periodic table; noble gas's stable; halogens and alkali–

They were atomic numbers.

Excited now, he checked his watch– he had three minutes until class officially started– and flipped the note over yet again.

54 – Iodine, I; that was easy.

115 – well, uh, if Copernicium was 111– Ununtrium, Flerovium, Ununpentium– Livermorium, Lv.

92 – also easy: Uranium–

I Lv U.

His thought process and excitement came to a screeching halt. Oh, crap, was this a love confession note? It couldn't have been for him– oh crap, oh crap– he was invading someone's privacy–

He noticed another set of numbers up top.

To: 18 25 / 18 3 111.

Well, if it wasn't for him, then he could at least find who it was really for and give it to them. He searched the table branded into his brain. Argon and Manganese, then Argon again, Lithium, and… Roentgenium. ArMn ArLiRg.

He assumed the Rg was meant to be an Rt (probably a memorization error on his own or the writer's part, or simply out of desperation from the lack of diverse atomic symbols) because there was no one in the entire school with a name even remotely like that except for his own, so that meant–

The bell rang at that moment, but he could hardly hear it from the amount of disbelief that was crowding his head. Only when the lights turned off and the projector flickered to life did he quickly hide the note and begin to take his own notes on what was being projected.

But, between slides, he solved the rest of the code, ending up with:

To: ArMn ArLiRg.

I Lv U. SCaVEsGeRe HUNTi TiO FINd MoI?

Or, as he scribbled beneath the cracked code (so that he couldn't get an aneurysm from trying to read it over and over again when the words were butchered so horribly):

I love you. Scavenger hunt to find me?

There was no signature nor any other hints as to the writer's identity, with the exception of perhaps their handwriting. He supposed that the whole anonymity thing was part of the mystery and scavenger hunt.

But how would he answer them? He knew he had to, otherwise he'd seem rude for ignoring them, and things could turn awkward.

He supposed Ms. Nanaba had to know about and allow the note to make it to him; she tended to toss papers left behind on desks in the recycling bin between periods. If she, for some reason, would allow the note to stay, then maybe she'd pass one back to the writer. Regardless of whether she agreed or not, it was his only guaranteed shot to getting the note to the right person.

Ah, but how would he word it? Just saying "okay" and then signing it seemed too strange, too uninterested. No, quite the contrary; if he didn't figure this out, he felt as if it would eat away at his conscience for the rest of his life.

Well, it was a code involving the periodic table; he could make a similar code back at them.

He paused his train of thought on the response to scribble down some notes.

There was Potassium, K, and Oxygen, O. They could realistically come together to make K2O, dipotassium monoxide. But that was backwards.

Backwards. He could write the word form backwards. That should get his message across in a sufficiently cryptic manner.

He ripped out a corner of his notes, scribbled his reply on it, folded it in his own way, and tucked it away until the end of class.

The bell rang soon enough, and as his classmates escaped to their next class, Armin went against the current and up to Ms. Nanaba.

"Uhh, Ma'am?"

She looked up from her desk. "Yes, Armin?"

He pulled the notes out, suddenly feeling a little embarrassed. "I found this note for me from a different period– it seems like that anyway– and, uh, know you throw our most scraps left behind, I figured there must be a reason–"

"Why?" she finished for him, smiling a bit and calming him down.

He nodded and showed her his own tiny, folded note. "And if you could give a note with my response to them."

She took it as she spoke. "I only helped her because she asked. That's all. Now hurry along to your next class. You've got five minutes left."

"Thank you!" he called as he left.

The next day, there was another note sitting plain as day on his desk. He slipped it into his pocket to solve later during lunch.

Author's Note i. Oh no, not another oneshot that spirals into a multi-chapter! ! ! well, at least this one isn't going to be 35 chapters long. i have the whole thing written out; it's five. maybe six if people want that kind of bonus content, but a solid five for now. the roentegnium thing was actually my fault lmao. i was writing in class w/o access to a periodic table so i referenced the one in my head and whoops turns out it's not actually Rt. got the number right OHHHHHH.

i literally started planning this like nine months ago. i'm not kidding you the riddles you read in this fic will be like nine months old. i just never really got around to writing it until like late may. for like a day. and then i stopped. and then i dumped out like 6k words today and finished it loool. anyway. follow or favorite if that's your thing. maybe review and validate me. if someone can crack a code i'll let them send me a request for a drabble and i'll probably write it. if you can guess the riddles that are actually fair (since a fair amount of them are based off the geography of my school whoops) then i'll write you two drabbles or so. if i like the prompt. which i probably will. yes.

leave a review, if that's what you're into, and as always, have a greaaaaaat daaaaaayyyy~~