Author's Note: The prompt came from tumblr user unnaturallyhungry. Enjoy!

Till Death Do Us Part

"I'm sorry."

"Shut up."

"I should've –"

"I said SHUT UP!"

Chase flinched, a hurt expression flashing across his face as Riley continued to bandage the festering wound on his arm. He didn't have the heart to tell him that none of his efforts would matter in the end, although he had a feeling Riley already knew, deep down, but refused to let himself believe it.

If the younger teen wanted to pretend that everything was going to be okay, even just for a little while, then it was all he could do to sit still and play along, because they both knew what the apology was for, and it wasn't the fact that Chase was about to die.

It was that Riley had to be the one to kill him.

They lost Kendall first.

The scientist had been at a conference in the city where the first wave hit. She had barely managed to call the museum to warn them before the phone line disconnected, and that was the last they'd ever heard from her.

Grimacing as the brunet taped down the last of the stubborn frayed ends, Chase noticed that Riley adamantly refused to look at him. His shaking hands occupied themselves with packing up the first-aid kit, and he was deliberately focusing on rearranging the remaining meager supplies in the dirtied white box, trying to ignore the small patch of black mould he knew was growing beneath the thick swathe of bandages on Chase's arm.

Embedded in the grass just behind them was a polished metal sword along with a pair of discarded guns a few feet away, empty magazines scattered around them.

It had been sheer, utter chaos during the evacuation of Amber Beach.

They had tried to stay together, but the crowd had ripped Shelby away from them and Tyler had gone back for her. The two were swallowed up by the sea of people in the blink of an eye, and Koda very nearly dislocated Riley's shoulder yanking him to his feet, preventing him from getting trampled by the panicking masses.

Riley started when Chase suddenly grabbed his hand. He tried to pry it off, albeit half-heartedly, but the New Zealander only tightened his grip. Sighing in defeat, he allowed himself to be pulled into his boyfriend's warm embrace, savoring the moment with him. The younger teen inhaled deeply, taking in the comforting scent of Chase underneath all the layers of grime and sweat. If he closed his eyes, he could almost imagine that it was just the two of them in the world, that in these precious few seconds nothing else mattered but him and Chase in each other's arms.

There was a sudden lurch and a tight squeeze around his chest. The back of his shirt started to feel wet, and Riley swore he could hear both their hearts beginning to shatter.

The ranch was gone, burned down to ashes on the ground with no sign of Matt or Mrs. Griffin. Riley was given a day to mourn before they left. The four of them managed to survive the first three months together, being careful, keeping vigilant, and never staying in one area for too long. There was no destination or safe haven to be searched for; all they knew was that they had to keep moving.

Koda and Ivan left to gather food and supplies one day. Chase and Riley waited for forty-eight hours before packing up and leaving camp.

They never looked back once.

"I'm sorry," Chase repeated brokenly, valiantly trying to keep the sobs at bay. "I don't – I don't want you to see me like – to remember me as one of them."

Riley only hugged back tighter, unable to swallow past the heavy lump in his throat. There was only one or two hours left before Chase turned, and he loved him too much to see him go through the agonizing process, watching him lose his last shred of humanity.

It was now or never.

The only problem with using swords to chop off animated heads was the fact that he had to get close enough to reach them. Fighting at close range had never really been an issue for him, but it was different when he was pitted against an enemy he couldn't afford to come into contact with.

Riley had thought he was done for, having been cornered into a dead end during a supply run. He was seconds away from slitting his own throat, prepared to buy Chase some time to get away while the hoard feasted on his dying body, when the other male charged in with guns blazing, shooting down a path of twitching corpses to drag him out.

Hours later, as they inspected the angry bite mark on Chase's arm, Riley's only thoughts were: You should have let me die.

Despite himself, Riley began to smile.

"C'mere hotshot," he whispered, nimble fingers sinking into the New Zealander's dark locks as he dragged his lips down for a kiss. He nipped lightly at Chase's trembling bottom lip, the taste of salty tears falling onto his tongue. The other male sobbed quietly before giving in, kissing back fervently as he lowered them onto the cold ground, caging Riley's body under his.

One hand curled around Chase's neck to keep him close, pressing them chest-to-chest, while the other reached out to the side and grasped the hilt of his sword in a loose grip. The sound of metal dragging on grass prompted Chase to break the kiss to look at Riley's face, and the sheer amount of raw devotion staring back at him left him breathless.

There was a determined glint in the brunet's eyes, and some part of Chase realized what he was planning to do. He smiled down at him and murmured a final "I love you" before claiming his lips one last time, with Riley's head surging upwards to meet him halfway. The younger teen raised his arms, keeping the tip of the sword pointed downwards, directly above Chase's heart.

Then he pulled.