Note: This could be construed as slash. Take it how you want.
A Will Without a Way
It was the third creature Crowley had brought back that day. He stared at the kitten in his hands, a moment ago drowned by some idiot kid. The kitten mewed up at him and tried to climb up his jacket.
"No, no, no." Crowley unhooked the kitten, but it scrambled up his shoulder and scratched his hand along the way. "Ow! F--" Crowley stopped himself before he said it. No more swearing. He'd gone without it for a week, and he was getting rather... peeved. And he knew it was going to take a lot longer than that. Part of him was thinking about giving up the endeavor, but he shook his head and called up the image of Aziraphale. That's what made all of this worth it.
The kitten rubbed its head against Crowley's and purred. He had a bad feeling he was going to have to keep this one. "All right." Crowley grumbled and stood up, the kitten still clinging to his shoulder, and walked to the Bentley. By the time he got back to his apartment, the kitten was on his head, and one if his shirt sleeves had been made into ribbons. He slammed the apartment door, frightening the kitten, which clawed him before leaping off his head. It raced across the room in a blur and leapt onto one of his shelves.
"No!" Crowley yelled, but it was too late. The cat had raced behind one of his plants and it crashed to the floor. What was worse, it was one of the few plants that hadn't drooped since he'd stopped threatening them.
"It's okay." Crowley cooed to the plant as he wrapped it in a towel. "Ow!" The cat jumped on his back and the two wrestled for another minute before Crowley could soak the towel.
He drove the Bentley at top speed to Aziraphale's bookstore. "You better be in there, angel." He grumbled. Fortunately, the shop was open.
"What happened, dear?" Aziraphale rushed to Crowley's side as he took in the tousled hair, torn shirt, and askew sunglasses.
"I brought you another plant." Crowley said, thrusting the bundle at him.
Aziraphale raised an eyebrow. "It's usually in a pot."
Crowley's free hand tried to fix the placement of his shades on his face. "My cat broke it."
"Azirpahale took the plant and examined it. "Since when do you have a cat?"
Crowley looked at his feet. "Since I brought it back to life..." He muttered.
"You... why did..." Aziraphale looked at Crowley's hunched shoulders and at last made sense of Crowley's behavior the last month. "You know..." his words were more quiet than Crowley's had been before, "fallen angels can't be redeemed."
Crowley pulled his sunglasses off. "But humans were redeemed."
Aziraphale looked into his friend's pleading eyes. "Because God became a human to redeem them."
"Why can't God become an angel?"
It made Azirphale wince to tell him the truth. "Humans are all of the same stock. Angels each come an individual stock. There's no way for God to be born of an angel."
"I could have children..." Crowley insisted. Whatever it takes, he thought.
Aziraphale shook his head. "Not with someone of the same stock as yourself. Even your children would be a different race than you." He put his hand on Crowley's shoulder. "I'm sorry. It can't be done."
Crowley's eyes never left Aziraphale's face. "You have to be wrong," he whispered, "You have to be."