Castiel flew down to Earth for what he thought was the last time; the last time he would see Dean Winchester, at least. Dean was where Cas left him, even though at least a day has passed.

'You came back this time,' Dean said, smiling.

'I had to say goodbye,' Castiel whispered quietly.

The smile dropped from Dean's face. 'What do you mean, "goodbye"?'

'I can't come down again,' the angel replied vaguely.

'Well why not?'

'Things came up. I've been advised to stay away from you. I've been told my involvement in your life is beyond my call of duty.'

'But what if I don't want you to go?' Dean asked.

'I don't want to go either, but if I don't, they'll make both of us forget. Sam too.'

Dean paused. 'You mean, I'd forget all about you? I wouldn't even know who you were?'

Cas nodded.

'And you wouldn't know who I was?'

'Not in the way that I do, no,' Cas confirmed solemnly.

Dean moved forward and pulled Cas into a hug, and the angel let him. 'I shouldn't even be here right now.'

'I must be pretty special then,' Dean commented, trying to make the angel laugh, but Cas pulled back to look at him seriously.

'You mean everything to me, Dean. I'm sorry for everything that happened, for not looking after you when I should have.'

'It's fine, Cas.'

'Dean, I love you.'

And this time Dean said it back, without hesitation, because this was his last chance to ever see Castiel in person. 'I love you too, Cas. I know it doesn't seem like it sometimes, but I have done for so long.'

Cas felt the tears fall from his eyes, and he held Dean even tighter, not wanting to let go, not now, not ever.

'Cas, I don't want you to go,' Dean said, voice breaking at the final sentence, and Cas looked up to see that the Winchester was crying too. Cas reached a hand to wipe the tears away.

'It'll be okay, Dean,' Castiel promised. 'I'll watch over you still. Just from a distance. So don't go getting yourself into trouble, okay?'

'I'll try my damnedest not to,' the hunter replied. 'I'm so grateful for everything you've given me.'

'It was my pleasure,' Castiel replied, because of course it had been. He'd given everything to Dean, and he just wished it could have been more.

'If circumstances had been different…' Cas began, trailing off uncertainly.

'Yeah,' Dean agreed, nodding as though he knew what Cas meant.

Castiel reluctantly pulled away, trying to extract himself from Dean's arms, but Dean pulled him back so they were pressed firm against each other, looking into each other's eyes, conveying thoughts they'd never be able to put into words. Dean leaned forward and kissed him, and Castiel kissed him back, wrapping his arms around Dean's neck so he could be closer, because nothing would ever be too close to Dean anymore.

'I need to go,' Cas whispered, breaking the illusion of safety and happiness.

Dean nodded, let his arms fall away from the angel's frame.

'Goodbye, Dean.'

'Bye, Cas.'