--Decided to make this world their home. Tempting as it might be, Aziraphale could never, could he? He couldn't abandon Earth to the eventual war between Heaven, Hell and mankind, nor could he abandon Crowley to fend for himself. Never. Their life had been on Earth (even if they were not human) and it had been together--as it had since the Beginning, no matter how much Aziraphale fought admitting so. He didn't belong someplace, but...
A quiet thank you, followed by: "I can't, I'm afraid. There is someone I can't possibly leave behind."
Was already in it, but gonna hit spoiler territory here
A quiet thank you, followed by: "I can't, I'm afraid. There is someone I can't possibly leave behind."