Late August, 1903. Ashford, Eastern Amestris.

The next morning, Roy had coaxed Riza into the shower with him, standing them both under the warm spray of water as he slipped his hands over her hips. The heat eased the dull ache in her body, and Riza had smiled as Roy's hair plastered to his skin, and rivulets of water washed down his chest. When he ducked his head to grab the soap, water hit her face, and she laughed in surprise, taking them both down in a fit of soapy laughter. They hugged, Riza leaning into his shoulder thoughtfully before Roy finally sighed and turned off the water.

"Consider that your send off." She had said, stepping out onto the bathroom rug, stealing his towel. Roy followed, biting his tongue as he took the remaining towel and brushed his hair back from his eyes.

"I'll take that with me, and remember it fondly." He'd said playfully, before she leaned up for one last kiss.

Getting dressed had happened alone, Riza stretching her arms and legs until she felt loose and limber again. Her toes had curled into her carpets as she slipped on clothes, pulling on a light blouse and shimmying into a dark blue skirt that reminded her of Amestrian uniforms in color. By the time her father had arrived home, her hair had dried, and any evidence to anything out of the ordinary had been locked away within her. Muscle memory kept Roy under her skin, invisible to anyone but herself. Even her clothes spoke to nothing unusual, and Riza braced herself for the storm that had yet to hit.

Avoiding Roy's official announcement of his departure for the Military Academy wasn't as easy as it had initially sounded. From her place down the hall, she could still hear the even and soothing convictions of Roy's voice against the increasingly upset timbre of her father's. While she had already expected the outcome, the severity of her father's voice as he told Roy to get out of the house still reeled her with shock and a sudden bitter taste in her mouth. It was final. But then, it already had been a final decision in Roy's mind. It just seemed too soon.

He was packed. And though she avoided going to him as he marched out of her father's study, she heard him call the taxi all the same, knew in the knot of her stomach that leaving meant now, not tomorrow and not at the end of the week.

It took less than an hour for him to pull his trunk and suitcase down the stairs and to the manor's front porch. When Riza saw the small black cab rolling down the far end of the street from her bedroom window, she rushed down the back staircase quickly, avoiding her father's ire to push open the front door, and catch one last glance of Roy Mustang. He startled when she exhaled in relief at having made it in time, and Roy turned, his black coat moving over his shoulders as he looked back at her. It was clear that she wanted to kiss him, and he hesitated, as if hoping that if he'd step closer, they would finish the action together, but neither of them moved as the car rolled to the front of the house.

"These are yours." Roy said quietly, handing the folded pages of their notes over to her. "I was hoping to give them back, so you could figure out what you wanted to do with them."

Taking them into her hands, Riza marveled at the clever addition of a green ribbon to wrap the bundle. For a soldier, of course. Not traditional letters home in any sort of sense, but she could keep it in her desk and consider the women who chose to wear ribbons in their hair again. Perhaps they couldn't be blamed for that small connection after all; though Riza was still convinced what she had taken was far more of a tether to him than a simple bow. If nothing else, she trusted him - and he trusted her.

That alone could move her forwards without regret.

"Thank you." Riza said quietly, looking at the cab driver who had stopped before she glanced back at roy. "Good luck, I suppose."

Roy nodded, reaching for his luggage. "Thank you. For that. For everything."

"I had better see you again, Mister Mustang. Maybe when you've graduated." Something hot pricked at Riza's eyes, but she blinked it away and smiled back at him.

"That's a promise." Roy said with a casual but forced grin. He hesitated, palming her shoulder for a moment before he withdrew his hand and sadness flickered over his gaze for a moment. "When you least expect me."

"You're only saying that because you plan to show up unexpected."

"Maybe." Roy laughed. "Goodbye, Miss Hawkeye. I'll think about you."

"You should focus on your studies." She said firmly. "Goodbye."

Roy laughed, something that was laced with a kind of pain Riza hadn't expected and wanted to take back, but his eyes were bright and she thought better of saying anything more. This was a moment of happiness for him, even if he was loathe to admit it - a purpose was what got Roy up in the morning. Instead, she gave him a slight nod in response, and watched as he loaded his things into the car and slipped into the passenger's seat, waving as the automobile pulled away and out of sight, leaving Riza standing alone on the front step of her porch.

When the car vanished from her line of sight, Riza turned, slipping back inside the Hawkeye household. She ghosted her way past her father's study, stopping only when he remarked to her from his seat at his desk, "That boy doesn't understand what he's thrown away. Good riddance." Berthold Hawkeye's lips twisted downward in disdain, underneath ragged bangs that spilled over his eyes, and guarded his face. The dust of his study swirled in the edge of light from the hall, keeping her father in a musty shadow. Coughing, Berthold returned to his notes, scrawling out complex formulas with dipped ink and an iron pen.

Riza inhaled sharply, but said nothing, face schooled in a blank and perceptive expression.

"It's just you and I again, little bird." Berthold said soberly. Adjusting his worn cravat as he leaned further into his books, he hummed lowly, pushing aside papers. It was the sound of a Master falling into his work - the magnum opus that Roy had wanted to obtain, and Riza had spent years watching her father finish. "Later this week, I will show you what I've learned from my trip. I think this is a breakthrough for my manuscript, and I need your help."

Riza nodded. "Of course, father. If you'll excuse me, I need to finish my studies." The last words trembled from her lips and she swallowed them back before fading away as her father grunted an affirmative. Berthold Hawkeye would return to his inkwell without a second thought, and it was clear that her father's eyes were already more intent on his work than they were on her. For once, Riza felt a rush of gratitude for their shared silences, and her father's slipping presence when confronted with his studies.

The wood creaked as she leaned away from the door frame and walked down the rest of the hall, stopping to stare at the shell that had been Roy's room, empty and gutted. It was strange, and she forced her gaze away from the opened door to duck inside her own room.

Locking the bedroom door behind herself, Riza collapsed into her bed, bundle of notes still in her hands. Fingers shaking as she loosened the ribbon, Riza let the pages spill across her bed, each filled with chemical equations, with notes, with words and phrases that Roy had added or thought amusing. It had become more than the experiment, within she found other code keys, alchemy notes on the properties of several metals, a jotted note on the illegality of transmuting gold, and lines of poetry he had been attempting to memorize.

On the last page, fresh blue ink had been printed neatly, and Riza laid it down before her, blinking back a blur that threatened to break her ability to read it:

'The amount of energy required to break a covalent bond is equal to the amount of energy released when the bond is made, and that value is known as the bond energy.'

Turning away from his words, she pulled a pillow to her face, and for the first time in a long time, Riza cried.

Well, Happy New Year's everyone! I have to say, I'm genuinely excited to say this is the final chapter of The Concupiscence Conjectures. This story ends here; and I'll admit, I am quite nervous about the ending, moreso than anything else, I had to have it feel "right". This is what I came up with, and I hope you agree with me. For those curious, and to clear it up: Roy's alchemy code was "Molybdenum, Boric Trioxide, di-Hydrogen, Chlorine, Cobalt, Silicon." [all body parts] and " K, H2, Cu, Li, Fe, S, Bi" all actions/doing verbs. It's ah, not particularly a difficult code to figure out if you've got a bit of a dirty mind and some free time on your hands. The final notes that mention metallic properties are also important and give us a good insight into Roy's mind/what he's not quite saying to Riza. The bits of poetry are Roy's attempts to seem romantic and to memorize more lines and codes and meters; it's not simply a matter of him trying to impress her, he's actually trying to improve his references breadth. Lastly, Roy returned the notes to Riza because they were not meant for him and he has absolutely no intention of making comparative notes on women. The idea bothers him a great deal, and it was more about Riza. It wouldn't sit right with him to keep her experiences on hand.

I hope you all enjoyed this very much, and I'm pleased to say that there will be a sequel, starting next Sunday! Please keep an eye out for The Logogriph Letters.