Hello stranger, come in and have a cup of tea, sit back, and relax.
John stays at Sherlock’s side through all sorts of marvelous, insane adventures in Faerie. They get in trouble with personages from the redcap to the Queen of Air and Darkness.
John’s eventually spent so much time among the faeries that he’s practically half-fae himself. He’s spent days as a jaguar, sleeping at Sherlock’s feet, and they’ve flown together as hawks with purple wings above the jeweled forests in search of a misplaced phuka, and swum as eels down between fallen columns in an ancient lake to solve a case with a kelpie (John remembers how Sherlock’s long smooth tail coiled tight around him and held him in place, and it makes his face go pink every time). One time he got turned into a tree by a curse and by the time Sherlock figured out how to break it, he’d borne fruit.
Sherlock ate one. It felt indecent.
But sometimes John gets to missing the human world, and then Sherlock will give him a gift and let him go walk among them again for a while. Sherlock goes along too, of course. He won’t risk John falling too far out of Faerie and back into the human world again. But truthfully, Sherlock enjoys it too. The humans are so WEIRD. And their world changes so interestingly from one year to the next.
They’ll gallivant all over the place and find ridiculous trouble to get into. Sherlock is absolutely enchanted by the human clothes and manners and social classes. Sherlock will spend days at a time in disguise, playing human dress-up and then ninjaing John into surprise sexual encounters in unexpected places, and he’ll learn rules just so he can break them. John spends the entire time being outrageously embarrassed by his dining companion, dancing scandalously arm in arm at rich parties, engaging in risky semi-public sex in sordid corners, and generally taking more enjoyment than he should in being made a public spectacle of while running and fighting and nosing into other peoples’ business.