So the THEN segment largely featured Cas(ifer).
The cold open was about a little gay boy whose older brother promised to get them both out of their little homophobic town, and then was body-snatched by the chitters leaving the little gay brother to suffer alone…
Then the setup to the hunt was Dean not sleeping because he’s worried about getting Cas back from Amara. He’s 100% worried about Cas.
And then the chitters turn out to be a huge glaring metaphor for “coming out” and being denied by family. “Sexually deviant” monsters that drive “nice people” into doing awful things.
But the little gay boy grew up, found love, and someone to support his quest to hunt down the things that took his brother. Together.
And now that they’ve come to the end of their mission, their job of stomping out the monster that lurked in their past and haunted them, they are literally going to ride off into the sunset together to start a horse ranch. With Dean’s blessing.
After Dean asked what it was like to “settle down with another hunter.”
Well alrighty then. I think that’s pretty clear.
…and to end their quest, they had to go back to the beginning…