Note: I do not own Supernatural or any of its characters. Ties in with the book, War of the Sons, but if you Google Eisheth's name, you should be able to understand this without reading the book.
"NO!" Michael roared, throwing himself against the door to the cage. "THIS ISN'T SUPPOSED TO HAPPEN! FATHER, PLEASE!" The archangel cried, rattling the bars. "YOU NEED TO LET ME OUT!"
Lucifer rolled his eyes. "That's not going to work."
With a growl, Michael departed from his vessel, letting it drop to the floor of the cage as the angel grew to his full height. "THIS IS YOUR FAULT! IF IT WEREN'T FOR YOU WE WOULDN'T BE HERE!"
Okay, that was too much. "My fault?" Lucifer departed Sam's body. "I BEGGED YOU NOT TO FIGHT ME! HOW THE HELL IS IT MY FAULT?"
"YOU'RE THE ONE THAT COULDN'T DEAL WITH DAD LOVING ANYONE BUT US! YOU'RE THE ONE WHO DISOBEYED OUR FATHER! YOU'RE THE ONE THAT GOT KICKED OUT OF HEAVEN! YO-"
"YEAH, AND YOU'RE THE ONE WHO THREW ME OUT! I BEGGED…" Lucifer faltered. "Begged you not to…to just listen to me…" He shook his head. "You don't like it here, Mike? Well, I've got news for you. I've been living here for millennia and it never gets any better." Lucifer paused to let the words sink in.
Michael opened his mouth, but just as quickly closed it. His face contorted, teeth grinding. And then, he fell to the floor. "FATHER!" He cried out. "YOU HAVE TO LET ME OUT OF HERE!"
Sighing, Lucifer felt some of the anger leave him. As much as he resented Michael forgetting them stuck in this mess in the first place, Lucifer's memory of the despair that had wracked his grace when he had realized that there was no way out was still fresh and he had done exactly what Michael was doing. "It's going to be okay, Michael." Lucifer said, quietly, and walked over to sit next to his older brother, draping a wing across Michael's shoulder. Before, Lucifer had been alone. Now, he had his big brother. Their graces intermingled instinctively, as they always had when one had been upset, leaving Lucifer no doubt that their combined power would find a way out of the cage.
It was a full hour (or possibly a full day; time was strange in the cage) before Michael gave a sniff and sat up. "So, what is there to do around here?"
Lucifer shrugged. "Nothing much." He smirked. "Or there didn't used to be!" He rose and stalked over to where Sam and Adam were huddled together in the corner. Seeing this, Sam quickly positioned his younger brother behind him.
"Stay back!" Sam growled, trying to mask his fear.
"Don't worry." Lucifer rolled his eyes. "Your precious brother will be fine." He reached forward and tore Sam away from Adam, throwing the older Winchester to the middle of the cage.
"Sam!" Adam cried out, starting to rise.
"Stay out of this." Lucifer ordered, pushing Adam to the side.
"What are you doing?" Michael asked, rising, as Lucifer approached Sam.
"This little maggot threw us both in here. You want something to do? Why don't we punish him for his sins?" Lucifer replied. Sam tried to scramble away, but Lucifer just yanked him back.
Michael frowned. "You're talking about torture. I will have no part in this."
"No, brother." Lucifer replied calmly. "I am talking about justice."
Michael scoffed. "Is that what they're calling it these days?"
Lucifer frowned. "That doesn't mean what…" Giving up, he shook his head. They were going to be in Hell for a while; Michael could learn about innuendos later. "He's the reason we're in here, Michael! He threw me in and that wasn't enough so he grabbed you, too! We're going to be here for…" Lucifer shook his head. "Father knows how long. And it's all because of him."
Lucifer could see the rage in Michael's eyes, but his brother held it back. "I know. But the punishment can wait until the wrong he has done to us is less fresh in our minds. If we do it now, we may deal out more pain than is just."
The Devil sighed. Leave it to Michael to want to reason in the midst of chaos. Oh, well. Lucifer needed Michael's cooperation and that meant regaining his trust. "Alright." Lucifer replied stiffly, and went to take his place next to his brother. It didn't matter much, he told himself. After all, it wasn't like Sam was going anywhere anytime soon.
Of course, Lucifer wasn't entirely right on that part. It wasn't long after that that Castiel descended into Hell, slipping through the bars of the cage.
"Brother!" Michael cried out, trying to reach out to Castiel. "Please let us out of here!"
Lucifer held no such delusion that the brother who had just helped imprison them would willingly, but he saw no reason why Castiel should be allowed a choice. After all, Michael and Lucifer were archangels and if they both wanted Castiel's aid, Castiel would either give it or perish. They both leapt forward, one intending to embrace, the other to imprison. Both hit an invisible wall. None of them had been expecting this, but Michael and Lucifer knew what it meant.
"FATHER!" Michael cried out. "FATHER, PLEASE LET ME OUT OF HERE!"
"FATHER! YOU CAN'T LEAVE ME HERE AGAIN! PLEAE DON'T LEAVE ME IN HERE!"
"MY SONS." A loud voice reverberated throughout the cage. "I AM SORRY, BUT YOU NEED TIME OUTS."
Then, the wall disappeared and the two brothers fell forward. A sense of loss permeated the cage, and they knew that their Father had left. Castiel had disappeared and taken Sam's body with him, but had neglected to rescue Sam's soul.
'Oh, well.' Lucifer thought. Souls were more fun anyway. One could slice and pry at them, then heal them up to begin again. He glanced at Michael, who appeared to be in a state of shock, staring up at the ceiling of the cage, as if their Father could reappear any second. 'Time to play the dutiful brother again.' Lucifer thought, and approached Michael. "Come on, Mike." Lucifer urged, pulling his brother away from his place and to the edge of the cage. "Let's sit down."