But Captain Jack Harkness singing Christmas carols to Castiel, though.
He couldn’t give a cream-filled cherry spice flip about the religiously significant ones, but he’s always loved the effect they have on people and the way the tunes endured (and changed) all through his time on Earth.
Some of them hurt, for different reasons.
He sings them anyway.
And Jack likes the way Castiel looks at him when he does it. The amused acknowledgment of irony; the softening smile. The barrage of Castiel’s curiosity, ferreting out Jack’s experiences at Christmastime: with war, with the USO, with London, with Torchwood. With so many people. Jack answers a few questions; evades others. Asks a few of his own.
Some carols hurt a little less now.