Disclaimer: Don't own Supernatural, don't own Castiel.

The Adversary

"Eliul," Castiel said. His voice had power, his sharp eyes cut like daggers through the air, directed at the figure in front of him.

The figure was unmoved. He half-smiled, his facial muscles tightening into something like a smirk, sickly and wrong. Jane could not understand it, but it sent cold shivers down her spine and filled her with unspeakable horror.

"So you came for the mortal?" Eliul asked. Derision was heavy in his voice, made menacing by sarcasm and hatred. He moved next to Jane and put his face close to hers. "What is she to you? Something special?" He tracked a finger down her face, cold and painful.

"I have sworn to oppose you, Eliul, and I will not allow you to harm innocents," Castiel said. So come and bloody save me! Jane shouted in her head. He was far away, across the whole room, why didn't he jump in and rescue her?

"Innocents," Eliul said, tasting the word. He looked down at Jane and leered, eyes dark, no warmth. The last vestige of humanity was gone. Jane saw the black eyes and, for perhaps the first time in her life, understood what evil was. "There are no innocents in this world," he said.

Castiel said nothing, but the lights flickered, and some deep rumbling, almost unnoticeable, felt in the bones, shook the room. Power crackled in the air. Jane could not explain it except instinctually, but she felt the greatness of these two beings, whatever they were. She felt the presence of something otherworldly, something so far beyond the scope of her experience that she could not begin to comprehend it. She closed her eyes and whimpered. Please God, I never did anything bad. Let this all be a dream.

The lights sparked out above her and Jane screamed, surprised she could get the sound out, expecting the very air to explode with all the power and tension, or maybe just expecting to get electrocuted. There was rustling all around her and she saw movement through her light-blinded eyes, ill adapted to the semi-darkness left by the exploding lights. The figures had hurled themselves at each other, moving beyond her scope of vision. One of them slammed the other against the wall, shaking the whole building. Jane couldn't tell who it was, the meager light coming through the dirty windows not enough to reach the dark corners. She hoped it was the bad one.

Suddenly, it was silent. Jane strained to see what was going on. With an effort, she ripped her head around and pulled something in her neck, barely noticing the pain. One of them had the other against the wall, held up impossibly, as if it was weightless, neck gripped in an iron hand. It was Castiel who had overpowered the black-eyed thing. Jane could see his face. It was terrible, turned in a way that was both awful and beautiful, anger and justice written across his features. The words came to Jane's mind: An avenging angel.

The thing laughed. Cold, chilling laughter that made Jane feel sick. Strangled as it was, it croaked out the laughter of despair and victory. "Kill this mortal coil, Castiel? I'll only find another…."

Castiel was angry, and he only gripped it tighter. "You will be defeated in your purpose," he said. He looked the thing in the eye as it laughed again and Jane shook in fear.

"You are outnumbered, seraph. We rise again, with the help of weak humanity…. The world will fall," the being said, hatred dripping through his teeth. Castiel watched it with mounting aversion, and something like horror in his face. The being only laughed harder, seeing his adversary pause, questioning.

The black-eyed man suddenly drew up his hand and raked his fingers across Castiel's right arm. Castiel flinched badly and almost dropped the thing, sliding it to the ground as he fell to his knees, but he kept his hand tight around its neck. As he knelt there the other being twitched and the laughter died away in its chest. Black smoke poured out of its mouth and even as its eyes went wide and hollow Castiel did not let go. A moment later and the smoke was gone, evaporated into oblivion.

Castiel released the body and knelt panting on the floor. Jane could not tear her eyes away from the sight, but she found she could move again. Whatever had chained her muscles together was gone. She walked up to the two figures, one crouched in pain, the other unmistakably dead. His eyes were open, clear but dead, empty of that thing that had inhabited them.

"What… the hell… was that?" Jane asked the kneeling man.

He glanced at her and stood up. He was cradling his right arm to his chest, the sleeve of his jacket coated with blood. Funny though, there were no tears in the fabric.

"A demon. One of Lucifer's army. I have been tracking him," Castiel said. He crouched down by the body, examining it, it seemed, but he turned away unsatisfied.

"A demon," Jane repeated blankly. She too looked down at the body. Typical, middle-aged guy, going bald and a little on the heavy side. Could have been her high school geometry teacher, or some guy she saw on the bus every day. She half-scoffed, open-mouthed, not willing to believe it.

"So what does that make you?" she asked incredulously, hearing her voice rise with hysteria, but deciding she was justified in this case.

"I'm an angel of God," the man said. Matter-of-factly, simply, looked her straight in the eye. Those eyes that were too deep, too piercing. They saw right into her soul. Jane shivered and heard the rustling again. This time she realized what it was. Wings.

"Okay… okay," she said slightly panicky, in the tone she used to calm herself down after she found out she had to take Chemistry 101 all over again if she wanted to graduate college. "There's a dead guy on the floor, and I just saw a guy kill him, and I'm in a freaky abandoned warehouse, and apparently, now I'm in an episode of Touched by a Freakin' Angel!"

"This," she gesticulated wildly around the room, indicating the dead man, the shattered lights, and the bleeding man in front of her, "is completely insane!"

"But it is true," Castiel said. He stepped towards her. "I'm sorry to have brought you into this, but it seems it was unavoidable. I did not expect Eliul—" Suddenly he faltered. His knees shook and he seemed close to collapsing. Despite herself and everything that was running through her head, Jane rushed to his side and supported him.

"You're bleeding all over the place. What did it—he—whatever do to you?" Castiel gave no reply, not that Jane waited for one. "Ugh, this is exactly what I do not need. I guess I have to get you to a hospital…."

"No," Castiel said firmly.

"Then what am I supposed to do?" Jane asked, the whiny tone creeping into her voice again. She just wanted to wake up at home and have all of this go away. "I have a bleeding angel on my hands and a dead guy in a warehouse—" she cast the body another frightened glance—"and this is like, out of The Exorcist or something…." She trailed off as she felt Castiel slump against her shoulder. "Dude, do not die on me! There is no way I'm explaining two dead bodies to the cops!"

"Do you know of somewhere safe?" Castiel said. His voice was strained, but he made an effort to support his weight.

Jane sighed heavily and somewhat shakily, feeling close to tears. "Yeah, yeah, I guess we can go to my apartment…. Anything's better than here."

"You have an apartment?" Castiel asked.

"Yeah, have you seen the college dorms? They're like, ten by ten cinder block cells. I signed up to get a degree, not live in a penitentiary." Jane tried to get a grip on herself. Okay, this going to be okay. Probably. "Let's get you out of here, angel boy. Before you bleed all this holy blood onto my sweater."