Cas didn't want to stay in the motel room but if he left, he doubted he'd be able to come back so instead he spent his time looking through the books Dean was examining. Except, they were useless. There was nothing about angels in there.
Cas thought he understood what the vampire had done. She been attempted to extract his grace by force which would mean it would be lost forever. All she had done was weaken it, so Cas figured he had about 4 days before it was too weak to stay with him, and would just fade away till it was nothing, which would be painful and turn him human.
Or he could go back up to heaven, and strengthen his grace so he could stay in heaven, but he wouldn't have the energy to take a vessel again. Maybe in a few thousands of years, but that was not likely. By that time anyone he had ever met, saw would be gone and turned to dust. He would have to watch Dean, Sam and Bobby waste away and die.
He couldn't see that happen. Being in a vessel, Cas knew the pain he could feel and how weak humans were. He knew the risks of death and hell, but could he really give up his 'life' he loved. He couldn't give up his family. The angels were his relatives, nothing more. The Winchesters and Bobby had given him a sense of belonging, a feeling of home no matter where he was.
Bobby was a father figure he could look up to and admire for all that he had been through and done. He respecting him for being there for Sam and Dean when there father clearly wasn't, just like his wasn't.
Sam and Cas may have had a rocky start, but Sam was an amazing hunter and after losing so much, Cas couldn't believe he was still fighting for what was right. Their friendship had grown and was important to Cas.
And Dean was…Dean was the reason he was here. He main reason he had stayed and he reason he had done what he had. He'd rebelled, killed and given up nearly everything for Dean. And Bobby, Sam, Jo and Ellen too but Dean had made it all happen. And after what had just happened...How could he leave? A chance to show his true feelings for Dean, something he'd tricked himself into believing were nothing more than physical attraction cause by his vessel. He knew now it was more than that.
How could Cas give up a life he had grown to love for a life he had tried to forget? What was the point of him going back to heaven and spending eternity miserable while he could spend 40 years experiencing earth and spending the times with those he loved? Cas was old enough to realise that the life he'd lived wouldn't have had any purpose without the Winchester family.
An internal existence did not equal life. And those who considered it such did not know what life was.
Cas was unsurprised to see it was Sam who was first back to the room. It was Sam who was surprised to not see Dean there.
"Where's Dean?" Sam asked, walking to the little fridge and grabbing two bottles out of it.
"He left." Cas replied bluntly as Sam passed him an opened one. Sam eyes narrowed as he examined the rustled up half-angel.
"He said he wouldn't leave."
"Well he did." Sam could tell from Cas' tone that something had happened, but he didn't want to push it further. Ever since Cas and Dean had met they were always fighting and arguing, but San knew that Dean liked Cas being around, and that he felt Cas was like another brother to him.
Dean didn't have a lot to believe in, but he sure believed in Cas.
That was important to Sam. He knew how important faith was, and it was good Dean finally had some.
"So…how you doing?" Sam sat opposite Cas and went straight to what was on Cas' mind.
"I don't know yet. I wanted to phone Bobby, he'd tell me what to do."
"Nobody can tell you what to do Cas, this is your choice, you can't ask other people to make it for you." Sam knew a little something about people trying to tell them how to live his life. It was not something he would wish on anybody.
"Dean certainly thinks it's his place to tell me what I must do." Cas slipped the drink and looked down, regretting his choice of words. No matter what, Dean was Sam's brother. And it was no appropriate to discuss such issues as what happened to him.
"Dean thinks you can't stay. He wants you to live a full life. He's just looking out for you."
"But I can stay."
"You'd be giving up everything Cas." He pointed out. Sam was conflicted about this whole issue. On one hand, it would destroy his brother if Cas left. On the other, it might destroy Cas if he stayed.
"Everything but my family." Sam half smiled at this comment.
"You'd be giving up hundreds of thousands of years."
"What's better though Sam? I could live 60 more years; I could be happy and free. I could learn to love and be human and do all the things I couldn't before. I could feel anything. I could finally learn why Anna risked her life to fall." Cas paused as Sam remained silent. "Or I could spend the rest of eternity in regret, watching everyone I once knew turn to dust. Watch you and Dean Die. Bobby, Ellen, Jo. I couldn't do that."
"But what about when you get old Cas? When you feel pain and hurt and anger? You think its hard now; it will be so much harder. Every emotion comes with a price Cas." Sam was sure in the same situation he'd go to heaven. But he'd been human his whole life and knew how painful and difficult it could be. It was cruel to wish such fate on a friend. Cas would most likely stay in the hunter life. And that wasn't a life at all.
"I understand Sam." Cas signed. "I'd like people to say they'd miss me when I'm gone. I want somebody to tell me to stay, because they couldn't understand it if I left. I want somebody to tell me they'll do anything to bring me back, like you and Dean do. I suppose I need to be needed." Cas finally admitted.
"You want that?" Sam was shocked. "Why?"
"Because maybe if I knew I'd already made a change in someone life, it would make it easier to leave or to stay. I'd know I've made a difference, done some good in the name of my father." he thought for a moment. "Maybe if I knew my time down here was important, it wouldn't be so hard to tell myself I couldn't do anymore. But I think I can. Down here, I could help the world. Sitting back, ignoring humanity in heaven like the rest of the angels seems like no life at all."
"Cas, you have changed Dean and I for the better. We're stronger now, you've taught us well and we won't be the same without you. But we can't ask you to stay."
"Why not?"
"Because you know you should leave. You just want an excuse to stay." Cas didn't tell him he already had an excuse to stay. The excuse just might not be valid though.
"I know."
"I suggest we both get some sleep. It's been a rough day and Dean won't be back for a while I'm guessing." Sam raised his eyebrows a little at Cas to see if Cas would tell him anything but he kept his mouth shut. They went into their separate beds, Cas lay on Deans and thought about the experiences he could have if he were human, and the eternity he would sacrifice if he were to choose to stay. Every moment longer he spent in this half-human state would make it easier to think of some reason to take the easy way out and go back.
He knew what he had to do.
It was shortly after Cas heard Sam's gentle snoring he decided to get up very quietly.
He grabbed a bowl from the table, emptying it's contents, and walked outside.
After looking around for Dean, someone he would liked to have seen at this moment, he walked around the back of the motel to a grassy patch he thought might be suitable.
He'd heard the angels discussing things kinds of things, mostly when a fellow angel did them himself, but he hadn't thought about it until now.
He sat the bowl from the floor and took a knife from his pocket. He ran the blade down his arm, applying only enough pressure for blood to spill out and allowed his blood to splatter into the small bowl. He looked up at the sky and began to chant in Latin.
"Castiel angelus Domini ego sum . Genitor, fac me humanitate et dimittam te, ut mihi sacrificet mihi de meo officio ruina signum gratiae cupide mundum creavit. Dabo domum in nomine tuo: et dabo vobis cor creata hominibus amans rursusque manu tua."
He felt pain welling up in his body as he finished it but said a last sentence in English this time.
"Forgive me father."
And that was it. He felt more pain that when the vampire was trying to rip the grace from his body and he collapsed on the grass.
All anyone saw from a distance was an intense beam of light as Castiel the angel was no more.