From Ennui Enigma: Holmes has a secret phobia
Day 6: A Mysterious Arrival
Content warning for snakes, beyond SPEC.
There were many things Watson did not write about. The opening of "The Musgrave Ritual" was absolutely genuine, but rarely did his stories get as close to Sherlock Holmes as doubtless many of his readers would like. He guarded his friend's emotions and secrets as best he could, presenting him to the world as a perfect reasoning machine. It was safer for Holmes that way: criminals and other antagonists could not take advantage of his flaws if none — or at least, very few — were made known.
It was a charade Watson kept up even after Reichenbach, and then again after Holmes's return and retirement.
No one ever knew, for example, that Holmes's fear of the snake in "The Speckled Band" ran deeper than a natural reaction to a close encounter with such a deadly animal. The Great Detective once admitted to Watson could not abide any form of reptile, not even the little common lizard — although Watson had yet to discover if the phobia ran even to harmless turtles and tortoises.
Watson was visiting 221B one day, after his second wedding, when Holmes received a parcel with no note from the sender. The detective opened it carefully, mindful of Culverton Smith's failed trick… and immediately dropped it to the floor, leaping backward up onto his armchair. Watson's astonished gaze met Holmes's fearful one. "Watson," Holmes said in a strangled whisper.
Watson took one step forward and looked down. In the parcel was a small but oddly stout brown snake, and… it looked as though it was dead, belly up and tongue lolling out. "Holmes?"
"It's alive, Watson, it moved," Holmes said hoarsely.
Watson looked down. He didn't doubt his friend, even in the grip of terror. Well, some animals were known to play dead to avoid trouble; perhaps a small, non-venomous snake could use the same defense. "How extraordinary." He put on his gloves, then carefully closed the parcel and tied it back up, noting some pinpricks in the cardboard as he did so. "We'll have to see if we can find a home for this little fellow — he's certainly not native to Britain."
"But who sent it to me?" Holmes's face was beginning to return from dead-white to a healthier hue.
Watson frowned. "Yes, that's a good point — who would know?"
"Clearly a warning, but against what?"
"Well, do you know someone who deals in exotic pets who could take care of this little one while we think?"
"Watson…"
"You may be terrified, but it's only a very little snake and he shan't hurt you, old fellow. I should like it if we could see him in a better situation."
"Oh, very well! I do know someone…"
A/N: I couldn't really think of a phobia for Holmes beyond the one it seems reasonable that he has, so here you go. :) And oh my gosh, I am a week behind, I am sorry! It has just gotten so busy over here, like I'm this close to being overcommitted. But we'll get there! No matter what, I definitely want to write and post the Christmas Eve/Day fics on time.
Oh! And the little snake is a North American hognose snake; they're non-venomous, and when putting on a brave hissy front won't do the trick, they roll over and play dead. I've seen a video on Tumblr of one doing that; it's ridiculously cute — if you roll them upright, they will roll back over as if to insist they're really dead!