Summary: Byleth doesn't take care of himself well enough and almost passes out.

"And… And… This concludes our… Our overview of high risk, high reward tactics in the… The history of warfare."

Marianne's eyes looked around the room, watching her peers' faces express varying degrees of concern. It was common knowledge that their professor often put others before him; whether it was making sure someone didn't get hurt on the battlefield, having everyone fed before the end of the day, or retrieving an item thought to be lost, he was always going out of his way to help. The lengths he would go, however, culminated in the man now walking back and forth in front of the chalkboard with slow, heavy steps, each movement leaving him short of breath, and making him prone to mistakes, leading to some of the students having to help clear things up for the others.

"Any questions?" he asked slowly, then sucking in a deep breath as he braced himself against his desk.

Ignatz raised his arm with slight apprehension, and Byleth called on him. "Um, in regards to sometimes using an unarmored ally to guard an armored one from magical attacks, does there need to be distance between the two still?"

"Uh, yes, that's… That's a very good question," he returned, his breathing heavy as he thought it over. "Um, so long as the unarmored one has… Has built up enough magical resistance…" Closing his eyes and pursing his lips, he swallowed the lump in his throat, the arm bracing him on the table shaking ever so slightly. "The… T-the armored unit… It—"

With a crash and a clang, Byleth had collapsed onto the floor! His arm had swept off a stack of papers to the side, sending the documents flying as the students jumped up from their seats. Taking initiative, Claude leaped over his desk and almost sprinted, tucking his legs into a slide as he began pressing fingers against the neck of the crumpled heap of teacher on the floor.

"Lorenz!" he shouted at the casanova, the latter's eyes wide in shock, now magnified by being called upon. "Hurry and get Professor Cazagranda!" Watching the violet-headed man book it out of the classroom, he turned his attention to everyone else. "Raphael, start stretching; we might need your assistance in moving the professor."

Marianne jogged around her burly classmate, approaching her house leader. "Um… I have some medical experience, if it can be of use," she suggested, trying to hold herself together as she saw Byleth, his breathing troubled despite Claude holding his head and shoulders up.

"I don't know what you're fully capable of, but for now just stay with him," he ordered, moving away from him and motioning her to crouch down and support the mercenary, catching heavy shoulders in her arms. "Do what you have to do, I'll get everyone else to act, too."

As the Riegan heir ordered Leonie and Ignatz to run out, Marianne looked down at her troubled lover, his eyes almost-completely lidded as his chest heaved. Letting his upper body rest on her lap, the top of his head almost jabbing into her stomach, she brought her hands against his cheeks, as she let the tips of her pinky fingers stroke his jawline. "Byleth, are you still there?" she asked, watching to see if he was still conscious, a low mumble answering her. "Stay with me, okay? We're getting you help."

A groaned resounded from his mouth, a hand slowly raising and flopping onto his shoulder. His eyes screwed shut from the strain, but once she took his hand into hers, his face relaxed slightly.

"Alright, Professor—oh my!" Manuela exclaimed, her hands shooting over her mouth as she saw the mercenary's pale face. Lorenz caught up to the physician, clearly out of breath as he leaned against the door frame. "At first, I was quite displeased with one of your own interrupting my lecture, but I can see the situation is quite dire!" The leader of the Golden Deer simply nodded. "Are you aware of his affliction?"

"It looks like exhaustion to me. I've already sent two of us to retrieve a stretcher so we can move him."

Professor Cazagranda nodded in approval, then began walking towards the invalid. "Miss von Edmund," she greeted, kneeling down to better see the man. "How is he?"

"He's still conscious, I think, I've been trying to speak to him."

"Very good, so you remember what I've taught you." Leonie and Ignatz ran back into the classroom, the stretcher haphazardly carried between them. "Alright, they're here. Let's move him!"

Tucking her arms under Byleth's legs, and with Raphael moving the armored upper body, Manuela moved him from the floor and onto the fabric of the stretcher. Claude and Raphael took to the ends, raising it off the floor as they moved past a heaving Pinelli. "It'll be easier on everyone if we just take him to his quarters instead of the medical wing, complications from exhaustion just needs rest to remedy it," she guided, the two young men following her. "I'll have to make my apologies to you two now, however."

"What for?" Raphael asked, his eyebrow quirking out of confusion.

"His quarters are up those stairs."

The first thing Byleth noticed as he woke was where he was—a bed. Not a cot in the medical wing that smelled of tonics and other chemicals, but his bedroom. The bedsheet had been pulled up to his neck, falling down as he tried to sit up, when sore back muscles let themselves be known, causing him to flop against the bed. His breathing became heavy from the strain as he stared up at the ceiling.

A knock came at his door, but it opened before he could answer, with Marianne making her way in, a tray in her hands. Her eyes widened at the awake man before she resumed moving closer, placing the tray on the nightstand.

"... How long was I out?" he said in a low voice, not wanting to strain himself any more.

After filling a cup with tea, she sat down in the chair—which he noted should be in the main room of his quarters. "You were out for… an hour or so."

"Really? And you were here the whole time?"

"Miss Cazagranda asked me to watch over you."

Byleth's expression became perturbed upon hearing this. "You… Shouldn't sacrifice your time in class for me, Marie."

Marianne brought the teacup to his lips, slowly raising it so he could sip. "I'm actually supposed to have her class right now, so this is for a grade." She placed the cup back onto its saucer on the tray. "And it's just an elective, it's not mandatory for me to be in the lectures at all."

"I see…" The two sat in silence until he tried to reach for the teacup, only to be stopped and have it handed to him. "Thanks."

"Byleth, you're wearing yourself out," she said, her tone somewhat critical. "You can't keep this up."

"It's my job, Marie, I have to make sure you're all alright."

As her eyebrows furrowed, she can feel something bubbling up inside her, but she brushed it off. "How can you do that when you're not alright?"

"Why does it matter?" he asked, passing her the emptied teacup.

"Because you matter, Byleth."

He sank against the bed, looking up at the ceiling again. "Do I, though?"

Marianne felt the fingers of her free hand clench tighter, and her jaw clenched slightly. "Yes, you do. You do matter."

"No, I don—" The sound of shattered ceramic filled the room as his head snapped towards Marianne, strained muscle be damned, her hand clenched into a tight ball as blood seeped its way out from between her fingers and palm, dripping onto the mess of ceramic shards under her. "Marie—"

"Don't call me that," she said, in a hushed voice, her grey eyes dulling as she looked at her injured hand, flexing her fingers and seemingly not minding the lacerations. Turning away without even looking at him, she walked out of the room, leaving the door open.

Evening had filled the sky when Marianne came back to bring Byleth dinner, her hand now thinly bandaged. Taking her seat again, she remained silent, refusing to look at him, her eyes containing a hint of bitterness.

As he slowly ate, he tried to look at the blue-haired girl, who continued to avert her gaze, and so he turned his attention back to his meal. A portion of roasted chicken with a lemon-butter sauce and a side of grilled asparagus—all delicious in theory, but its taste seemed too bland with how glum the room's atmosphere was. Laying the fork and knife down to the side of the plate, he stared at the food, pondering.

"I shouldn't have gotten mad," Marianne finally said, still looking off to her side when Byleth turned to look at her. "It was foolish of me—it didn't change how you felt, I've hurt myself, and… I broke a teacup."

"Marie—" Seeing her flinch at the nickname, he mentally reprimanded himself. "Marianne, can I see you, please?" When she didn't respond, he moved to place the tray onto the nightstand and kicked his legs over the side of the bed to better face her. "Marianne, after you walked out, I did start doubting myself." Catching her peek at him from the corner of her eye, he continued. "And, y'know, we both hurt ourselves trying to care for who we love."

"We did, didn't we," she returned.

"Then, can I make a promise to you?" he asked, answered by a soft nod. "I swear, if I find myself falling from this point forward, lest you begin to worry yourself, that I will come to you."

Marianne stood up, her hands held in front of her waist. "Then, I will catch you, and mend your broken wings."

Byleth also stood up from his place at the edge of the bed. "Then, can I start calling you Marie ag—" His head tilted down, seeing Marianne pushing his dinner tray into his chest.

Although her eyes remained stern, a smile slowly returned to grace her features. "Eat your dinner first."

Author's Notes: Okay, I just wanted to get a sickfic or something close to one in.

A bit more dramatic, this one.

Again, the Berkut blood coming out (literally).