A/N: Warning: This contains spoilers from The Script Leak of '17.

Basically, I started dreaming this up right after 4x11 aired, and I wanted to get at least the beginning posted before 4x12 completely ruined all my super-shippery headcanons. #sorrynotsorry?

Bellamy

Bellamy watched in horror and anger as Clarke nodded, then walked out the door, her spine ramrod straight, even as he saw her lower lip tremble slightly.

Abby shot a glare at Octavia, then turned it on him for a moment before she jogged out after her daughter.

Kane, meanwhile, stared after them both, then sank down onto the couch, his head in his hands as he released a long sigh.

Bellamy turned to his sister, who was standing behind the desk, her face unmoving. "O, you can't do this!" he repeated.

Octavia turned to look at him, her eyes betraying a moment of uncertainty before the veil quickly fell again, turning her back into the no-nonsense leader she'd become. "Bellamy, I have to."

He walked closer, his eyes beseeching, his tone pleading, "There has to be another way…"

Octavia let out a frustrated sigh. "I told you, everyone found out about Skaikru stealing the bunker. They were ready to stage a mutiny. You know exactly what that would've meant. Every single one of us would've been tossed out on our asses…or maybe just rounded up and killed. This is the only way…I promised them the leader who planned the deception…and that's Clarke."

"They don't know that!" he shouted angrily.

Octavia raised her perfect brows in a challenge. "So…what? You want me to condemn an innocent person to death instead? Who should I pick?"

Bellamy let out a frustrated huff, closing his eyes for a minute. "No, of course I don't. But…"

"Yeah, I know, big brother. It's Clarke."

He opened his eyes, catching his sister's gaze. She looked almost apologetic for the first time.

"It has to be her, Bellamy. She's the one who did this, and the grounders all think of her as our leader anyway. I doubt they'd believe us if we even tried to lay the blame on someone else."

Bellamy shook his head angrily. She wasn't wrong. Fucking Wanheda. He'd always hated that name, but never more so than right now.

"Bell…go tell her…"

He looked up when his sister paused, finding her watching him sadly, her eyes full of too much information he didn't want her to have.

"Go tell her goodbye," she finished quietly.

He shook his head again, refusing to admit defeat, then turning on his heel and walking out the door.

He traveled quickly in the direction Clarke had gone, finding her in the tiny room she'd claimed just a few hours prior.

He didn't waste time with pleasantries, instead just walking inside and standing behind her, hands on his hips as he watched her pack her meager belongings back into her backpack.

"Where's your mom?" he asked, finding Clarke alone.

Clarke didn't even look surprised to see him there, just glancing at him as she continued stuffing clothing and medical supplies in her bag. "She has some plan about getting Kane and Jaha to change your sister's mind. I tried to tell her it won't work, but she's in denial about…me leaving."

"I…I tried to talk to her…but she isn't listening," Bellamy admitted, beyond frustrated and well into panic.

Clarke shrugged one shoulder, smiling a little sadly as she turned toward him, grabbing her notebooks off the desk and dropping them in her backpack. "Honestly, she's doing the right thing."

"Clarke, how can you…" he started to ask incredulously.

"I probably would have done the same thing," Clarke admitted. "It's about saving as many of our people as possible, right? This way, 100 of us will survive. Had she done nothing, none of our people would have. At least this way…" she looked up at him. "I know the people I care about will be safe. If I have to leave to make that happen…I can live with that."

Bellamy was so far into a state of fierce denial about her leaving, he almost missed her pointed look at him as she talked about the people she cared about.

…almost.

But he did notice it…and it left him with one very clear thought.

Sometimes, it's about saving as many people as possible.

And sometimes, it's about saving the people you love the most.

He grabbed her arm so quickly, she jumped a bit in surprise. "I need to do something. Don't leave until I get back, okay?"

She eyed him warily. "Don't do anything stupid, Bellamy."

"I'm not."

She looked at him like she didn't quite believe him.

He gave her a slight smile. "I promise. I'm not going to start a war or anything. Just stay here, okay?"

She was still eyeing him worriedly, but she nodded.

He jogged down the hallway, to where his belongings had been placed.

Luckily, he hadn't had time to unpack yet, so he just grabbed his backpack off the bunk and his jacket off the back of the chair, then quickly made his way back down to the office where he'd left his sister.

He found her alone inside, staring at the computer screen that indicated how much radiation was present outside.

She glanced up when he shut the door behind him, took one look at his backpack, and said, "Oh, hell no, big brother."

He set his backpack on the floor, dropped his coat on the couch, and walked closer to her. "O…" he began quietly, his voice steady and sure.

"No!" she insisted, stepping around the desk and planting a hand in the center of his chest, shoving a little. "You are not sacrificing yourself for her. I won't let you."

"I'm not sacrificing anything, Octavia. I…" he sighed, looking away as he tried to figure out how to explain why he had to do this. "You and Clarke…you're the most important people in my life. And you're going to do great here. You've got 12 clans worshipping you after winning the conclave. You're going to be in charge of what's left of the entire human race. You'll have food, and water, and clean air…" he stepped closer, putting his hands on her upper arms. "I don't need to worry about you anymore. I mean…I'm always going to…but you're an adult, and you're stronger than I'll ever be. You don't need me to protect you anymore. If I let Clarke walk out those doors alone…"

Octavia was watching him with an angry look, although there were also tears in her eyes. "I could make you stay."

He sighed. She could. Miller and the rest of the guards had already shown they weren't going to be loyal to him. Hell, even Murphy had sided against him. "I know you could. But I'm asking you not to."

"Bellamy…if you go out there…you're going to die…"

"Come on. If anyone can figure out a way to survive, it's me and Clarke. Have more faith in your big brother than that," he wasn't quite sure he believed it, but he was trying. "They're going to hold a lottery anyway. I don't deserve special treatment. Give my spot to someone else."

She continued looking at him warily.

"You don't need me anymore, O." He said quietly. "But…I need her."

Octavia sighed, looking somewhere near his chest. "I always knew she was going to end up getting you killed."

Bellamy wrapped his arms around his little sister. "I love her," he said quietly against the top of her head.

"I know. That's the only reason I'm not killing her myself to end this stupid suicide mission."

"…thanks?"

Octavia pulled back, looking up at him fiercely. "Five years…five years and your ass better be knocking on that bunker door, asking what's taking us so long. You understand me, big brother?"

Bellamy nodded, trying to fight back tears, knowing that this very well may be the last time he got to see his baby sister.

She threw her arms around him again. "You're an idiot," she murmured.

He snorted, knowing he couldn't exactly argue with that.

"I love you, Bellamy," she said, the words coming out just as fiercely as she said everything else.

"I love you too, O."

They finally pulled themselves apart, and he walked to the door, grabbing his things as he went.

This time Octavia was the one to say it. "May we meet again."

He tried not to cry, really he did. "Damn right we will."

He took one last look at her, trying to remember her like this…as the strong warrior who could take care of herself. He knew it would let his conscience rest a little easier for whatever time he had left.

He opened the door, leaving his little sister behind, which is something he never thought he'd have to do.

He'd done a lot of things he'd never thought he'd be capable of since landing on this godforsaken planet.

But then he took a few steps and saw the back of a blonde head of hair hurrying down the hallway, the rest of her body obscured by a radiation suit, and he knew he was making the right decision.