"Okay, everyone ready?" Dr. Robotnik asks once they're successfully through the weapons bed. He doesn't wait for an affirmative before continuing. "Shadow, Rouge, on with the show!"
Before Shadow can actually start his part of the plan a body tackles him from behind. "Oh, Sonic!" a young girl's voice all but singsongs in his ear. "I thought I'd never see you again! I'm so glad you made it!"
He turns as best he can in her arms to see a kid who can't be older than twelve with pink hair and wide green eyes. When their eyes meet, she realizes her mistake and releases him. Shadow's entire world lurches. There on her bicep, where the skin had brushed against his neck—the side facing away from her now—is a telltale glow.
"You're not Sonic!" she continues as Shadow tries to process what this means. "Who are you?!"
"I'm the one who should be asking that," Robotnik cuts in, saving Shadow from having to find his voice and come up with an answer.
"Dr. Eggman!" she cries as the glow fades out, and Shadow finally turns the rest of the way to her. Having a new soulmate was never a factor in his plans, but as the shock wears off, he knows he can't let it change things. Besides, Maria is his soulmate, and he will avenge her.
"Ah, Amy. Your timing is impeccable," the doctor declares, finally placing the girl. Shadow watches as she tries to run away, only to find herself trapped between Robotnik and the ocean. "Leave it to me, I'll take care of her," he continues in an aside to Shadow and Rouge. "You two, go!"
And just like that, Shadow's soulmate is dismissed. Rouge and the doctor must have noticed the glow, but they're no more interested in pursuing that topic than he is.
Shadow doesn't see Amy again until the ARK is on its crash-course for Earth. He's watching the planet's rapid approach when she runs up to him for the second time.
"Shadow, we need you! Please, help us!" she begs.
He doesn't bother turning to her, not wanting to see the disappointment that will inevitably bloom on her face. "It's all going according to plan," he tells the window, gesturing at the planet beneath them. "There's no reason for me to help them. Besides, there's no way to save anyone."
"There has to be!" Amy protests. "I know that people fight over the most trivial things. Some people may be selfish, like the professor said... but they're basically good, if they try their best and never give up on their wishes. They always have a reason to be happy; that's why you should help them out! Saving them is a good thing!" As she speaks, memories of Maria flood back.
"Shadow, I beg you, please do it for them! Give them a chance!"
His heart stutters against the cage of his ribs. Maria begged him to give the people of Earth a chance to be happy, too. How could he forget? That's what he promised her, and he must keep that promise... that's what Maria wished for...
A tear slips down his cheek as he realizes the depths of his failure.
"Shadow?" Amy starts, but he can't afford to continue this conversation.
"I've got to go now, I have to keep my promise to Maria...," he turns to run, but pauses to make a final concession, "and you."
He doesn't see Amy again before he dies.
As stated at the end of my last fic, I wanted a fluffier project. Unfortunately, everything I touch turns to angst. I'm trying, though.
Fair warning, I have only the loosest outline for this fic. I have no idea how long it will be, and updates will be incredibly slow because this is my first draft.
Also worth noting that this is a soulmate AU and a human AU, because the way I wanted to do soulmarks for this specific story only worked if they wore clothes, and I don't like writing Mobians that don't normally wear clothes wearing clothes.
(I'm fine reading it, but idk. Weird hang-up, I know.)
Special thanks to chiniris and 81 from Ao3 for helping to beta this.