Sam and Dean were as good as dead.
It had started out as an ordinary crisis, as far as a life-or-death breakneck adventure can be called ordinary. Some upstart kid with more brains than sense had gotten his hands on a dangerous book and decided to become the next Alexander the Great. Nothing the brothers hadn’t dealt with a hundred times.
But this time, it seemed like they were well and truly toast.
Dean blamed himself. It was an obvious trap in hindsight, and he’d led Sam right into it like an idiot. Now they were stuck on the wrong side of a dark basement, a wall of steel bars standing between them and the wannabe sorcerer, who had begun chanting a passage from the book.
“You don’t know what you’re doing, kid,” Dean tried to reason with him for the tenth time, his voice hoarse. “Messing with occult stuff never ends well. You have no idea what you’re dealing with.”
The young man, barely more than a boy, ignored him and continued chanting the spell. Energy began to crackle in the air around him. Dean could already tell that whatever spell he was casting would likely end in the vaporization of both the caster and anyone else in the immediate vicinity.
Which, unfortunately, included him and Sam.
C’mon, Cas, he prayed, pressing his head against the bars. I don’t know where you’ve been or why you’re not answering, but we could really use a last-minute rescue right now. He glanced guiltily at Sam, who was still diligently searching for an escape from the sealed basement. At least get Sam out of here. He doesn’t deserve to die like this. I don’t know if anyone is even listening right now, but someone, please, protect my brother.
With a sigh of resignation, Dean turned his back on the doom unfolding before them and waited in vain for Cas to show up and save the day. Deep down, he knew Cas wasn’t coming.
One second, there was not a white-haired man standing in front of him. The next second, there was.
Dean barely had time to let out a squawk of surprise before he was sent crashing to the ground underneath a tangle of flailing limbs and screeched curses.
“What the-” he heard Sam say while he struggled to extricate himself from beneath the black-clad figure. “Aziraphale? How did you-”
“Oh, we came as soon as we heard Dean’s cry for help!” Aziraphale wrung his hands nervously as he took in the situation. “What have you poor boys gotten yourselves into?”
Crowley- of course it was Crowley, the bastard- sprang to his feet, managing to kick Dean in the chest on the way. “Oi!” he shrieked, incensed. “What gives, angel?!”
“Didn’t you sense it?” Aziraphale fretted. “These boys were in trouble! Of course we have to help!”
“And you couldn’t have given me five seconds to get off the bloody ladder before teleporting us halfway across the world?” Crowley demanded. “They weren’t even praying to us !”
“Time was of the essence!” Aziraphale insisted.
“Oh, so I don’t have time to get down off a ladder but you have time to lecture me, is that it?”
“Uh, guys?” Sam said. “I hate to interrupt your little domestic dispute, but we’re sort of about to die here.”
All attention immediately turned to the sorcerer, who had not broken his rhythm or, indeed, seemed to notice the newcomers at all. Words flowed from his mouth of their own accord, and Dean doubted he could stop now even if he wanted to.
“Worry not, dears. We’ll take care of this.” Aziraphale and Crowley exchanged a loaded glance. It felt like a silent argument passed between them, albeit one with a foregone conclusion.
Crowley sighed heavily, ending with a prolonged hiss. Then he collapsed facedown.
By the time he hit the ground, he was an enormous black snake. He slithered through the bars, his sinuous body easily passing through the gaps, and started to wind himself around the sorcerer’s legs.
The boy looked down in alarm as the serpent climbed up him, wrapping itself around his waist. He continued to chant, sounding more and more desperate, as he struggled against the snake, sparks of magic zapping them both like bolts of electricity.
Crowley didn’t seem to mind the shocks. He coiled himself around the boy’s chest and shoulders, completely immobilizing him, before he began to squeeze.
For the first time, the spell was interrupted as the boy wheezed, his mouth still moving of its own accord. The book fell from his hands as he grasped desperately at the serpent’s coils, trying in vain to free himself.
After a long moment, the occupants of the basement heard a sickening pop. The would-be sorcerer’s eyes bulged in his head as his ribs began to crack under the pressure. Blood leaked from his mouth as his face slowly turned purple.
Crowley shifted his coils upward, wrapping himself around the boy’s neck. His mouth continued to move silently as he gasped for air. Crowley hissed something inaudible into the boy’s ear before tightening his grip beyond the breaking point.
With one more horrifying crack, it was over.
Crowley slithered to the floor as the boy’s body crumpled. For a long time, no one said anything.
"That was... gross," Sam said in awe.
The snake reared up and in an instant, Crowley was back in his human form. He didn’t seem at all bothered as he searched the corpse for the keys to the barred gate.
“And for my next trick, I’ll swallow him whole,” he said flippantly as he unlocked the door. Dean’s stomach turned.
“No you will not,” Aziraphale said.
Crowley grinned menacingly. “You’re right,” he agreed. “I already ate.”
Sam started to walk past him and stopped. "So... are you a python or a viper? Are you venomous?" he said curiously.
Crowley bared his fangs. "Want to find out?"
Sam shivered. "No." He quickly moved out of striking range.
Dean stopped before he exited the cell and regarded Crowley skeptically. “Why did you save us?” he asked.
“It was the right thing to do,” Aziraphale cut in.
“Oi! I didn’t see you doing any saving!” Crowley said indignantly. “Butt out!”
"I could never deprive you of the chance to play the hero, dear," Aziraphale said patronizingly.
Crowley rolled his eyes, but he was still focused on Dean. “I’m protecting my investment,” he said finally. “You can’t do me that favor if you’re dead, can you?”
Dean’s face hardened. He thought it would be something like that. “Does that mean I owe you two now?”
“You wanna start keeping track?” Crowley said in the same flat tone.
They glared each other down.
“What do you want?” Dean said through gritted teeth.
Crowley pretended to consider. “How about a ‘thank you?’”
Dean would rather have owed him a second probably dangerous and potentially embarrassing favor, but he swallowed his pride for once.
He saved Sam.
“Thank you,” he said stiffly.
Crowley smirked. “You’re very welcome. Now, if you don’t mind, Aziraphale and I were in the middle of something. Although I’m sure all the scorpions have escaped by now, so we’re in no real hurry.”
“Scorpions?” Sam asked.
Crowley did not elaborate. Instead, he grabbed Aziraphale’s hand. “And if you boys ever get in trouble again, feel free to call…” he gestured with his free hand. “Someone else.”
And with that, the strange pair were gone.