Takes place right before Buffy is brought back to life in episode one of season six.
It felt amazing, being able to swim underwater and not having to hold her breath. Buffy's heaven consisted of a large pond that she swam in regularly. And the best part of it, when she got out and went back on land, all she had to do was think and she would be dry and her swimsuit would be replaced with regular clothes. This was absolute paradise to Buffy. The only downside is, she had this paradise all to herself, but she had no one to share it with. Well, except for one. Though technically he wasn't actually a person. As Buffy walked to a stone bench placed in front of the pond, she saw the bright out of the corner of eye. She looked up to see it descending, the light then began to grow in size as it formed into the shape of man. To the average human, this light would've been unbelievably overwhelming, but Buffy just smiled at it.
"Hello Castiel." Buffy said to the light.
"Hello Buffy." replied the light "How are you today?"
"Oh you know, same old same old. Swimming, relaxing, enjoying eternity in paradise. How bout yourself?"
"I am...well as you would say." said Castiel. Buffy chuckled slightly at his lack of human communication knowledge. Buffy then stood up and stretched slightly.
"I think I'm gonna take a walk around the garden, care to join?" she asked extending her hand. Despite that an actual face was not visible, she could somehow sense one forming on his face as a patch of light that had formed into the shape of an arm and a hand. This hand took hers as they suddenly found themselves in a beautiful garden.
"I looked into your friends and your sister." Castiel began as they started walking.
"How are they?" Buffy asked slightly worried.
"They seem to be well. They have taken it apon themselves to continue your duties, along with the vampire with fake yellow hair." Buffy just chuckled even harder at Castiel's description of Spike.
"And how's Dawn?", Castiel hesitated answering for a moment, which began to worry Buffy again.
"She is well, but she misses you terribly." Buffy felt a strong sting of guilt. Her happiness came at the price of leaving Dawn alone. Despite her peace, she still missed everyone horribly. But she was also at peace with the fact that they were safe and strong. She had no doubt they would all be able to live on without her.
"And there is something that is slightly troubling." This got Buffy's attention "You're friend Willow-" Buffy cut him off.
"Will? You just told me she was ok."
"She is, but she has obtained certain items that worry us."
"Certain items? Like what?"
"Items of a powerful nature. We believe she is going to attempt a very powerful spell. Possibly a very dangerous one."
"...Way to put a damper on my good mood." she replied with both a mix of worry and annoyance in her voice.
"I...I'm sorry Buffy. I didn't mean-" Buffy cut off his stammering once again.
"No, it's ok Castiel. I'm sorry, I didn't mean to snap at you." But Castiel went quiet again.
"There is also something else you should know..." Castiel had been hesitant to tell Buffy this, but he felt she had a right to know. "The hellmouth has been active lately."
"Well yea, its always active." replied Buffy feeling a slight sense of relief.
"No you don't understand. It's been more active than normal. We think something is coming, and whatever it is, its big." Any relief Buffy had was washed away in that second.
"How big exactly?"
"...We might have to deal with it ourselves, in person." Buffy stayed quiet for a moment, then spoke.
"You need me, don't you?" Buffy didn't expect Castiel's hand to leave hers and move to her shoulder. With that Buffy turned to face him.
"You've done your part Buffy, you've given everything you possibly could in the service of mankind. And I promise you, that if anything happens, we will deal with it ourselves." Buffy still looked doubtful, but Castiel continued "And I promise, I will personally keep your friends and sister safe should anything happen." Buffy looked at him again, but this time with a look of hopefulness.
"You mean that?"
"Yes, I do." Castiel was very unfamiliar with human contact as well. so when Buffy hugged him, he was not too clear on what to do next. He believed that closing his arms around her was the appropriate thing to do. But in that moment, Buffy looked up at Castiel. Though he had no visible face to her, she placed in her lips in area where she believed his cheek would be and planted a small kiss. But after that, Buffy began to go limp in his arms.
"Buffy? Buffy what's wrong?" he asked slightly panicked.
"I... I don't know. I just feel dizzy." Buffy began to feel lighter and lighter, until she looked at her hand. It was beginning to disappear right before her eyes. But Castiel could see that her entire body was vanishing. "Castiel what's going on?!"
"I don't know, I've never seen this before!" But Buffy began fading more and more."
"Castiel!" she cried as she faded away completely. All Castiel could do was just stand there.
"Buffy?" he just said quietly to himself."
Disclaimer: I do not own the rights to either Buffy or Supernatural. This all just fun and games.