So far, Gladstone the dog has been, well, a dog. But I don't really see either Sherlock or John as being dog people in this version of the classic story. So here's a re imagining.
John eyed the strange-looking creature on the table. It stared back at him with cold, emotionless eyes and a strange almost-smile.
"Why a giant spider?" John asked. Sherlock looked up from his notes.
"It's a Grammostola rosea, a Chilean Rose tarantula, approximately 6 moths old. You have been taking more shifts at the hospital. I need something to talk to in your absence and Mrs. Hudson threw out my skull." Sherlock smirked slightly. John rolled his eyes.
"So I am being replaced by a great big furry spider. I hope it bites you." John said, still observing the tarantula in its container. It stared back.
"The bites are not dangerous. Tarantulas are gentle creatures until provoked." Sherlock walked over and reached his hand inside the tank, letting the spider crawl onto his arm. It sat there calmly in Sherlock's hand. "Gladstone has been quite helpful today."
"Wait, you named that thing?" John asked incredulously. "That thing, has a name."
"Don't be idiotic. Of course he has a name." Sherlock snapped. "I would have thought you'd enjoy having a pet."
"A dog is a pet. A cat is a pet. A hamster is a pet." John pointed at the spider in Sherlock's grasp. "That is a heartless, soulless, beady-eyed monster."
"Some would say the same about me." Sherlock said softly. John sighed. "If you are truly so against him, I will find a place for him."
"No, keep him. If he makes your work easier, I see no reason to get rid of him." John suddenly became serious. "But I am not touching it, picking it up, or feeding it."
"Understood." Sherlock agreed. "I take full responsibility."
"Who are you and what have you done with Sherlock?" John joked. "Where did you even get it?"
"Lestrade busted a heroine dealer that had Gladstone as a pet. I took it off the evidence locker's hands." Sherlock watched as the fuzzy thing began to crawl up his arm. "He would have died in there without proper care, and it was obvious by the way the locker's keeper was looking at Gladstone that he wouldn't have survived the night."
John watched in fascination as Sherlock played with his new pet. Playing, as in Sherlock was content to let it crawl all over him and spider seemed content to do so. John had never seen Sherlock show any kind of affection for any animal. He was never cruel to them, or abusive, but he avoided them. But John supposed that perhaps the spider, no the tarantula, was something of a kindred spirit to Sherlock. It was misunderstood, avoided by most, even feared, and left alone to fend for itself because no one could be bothered to take it in.
"Sherlock, why Gladstone?" John asked suddenly. "Why that name?"
"Last name of his former owner." Sherlock said dismissively.
"You named your pet tarantula after a heroine dealer." John raised an eyebrow. "Of course you did."
Sherlock placed Gladstone back in his tank carefully, and placed the lid back where it belonged. He handled the arachnid as if it were a fine diamond or a delicate glass sculpture. In the tank, John saw the normal bedding and a plastic cave decoration as well as various rocks and some webbing. It was a nice enclosure, and all of it looked new. Obviously Sherlock had bought everything.
As time went on, John grew less repulsed by the creature and more inclined to tolerate when Sherlock let in run around the kitchen table. Gladstone never bit Sherlock, and Mrs. Hudson steered clear of it. John had eventually given in and picked it up a few times to return it to its tank before the landlady killed it with a broom. Gladstone felt like he was covered in toothbrush bristles, not soft but not spiny. John swore that Sherlock's pet watched him from behind the glass.
Approximately two months after Gladstone entered the flat, John started taking him out of his tank whenever he he was at the table. Watching the tarantula go for a "walk" was rather relaxing. Sherlock seemed to think so too. He once watched for four straight hours, occasionally feeding Gladstone crickets to "study the hunting behavior". John wasn't sure why, but Gladstone often sat quietly on Sherlock's shoulder as the detective conducted experiments, played the violin, or just sat motionless in thought during cases.
Mycroft had been introduced to Gladstone, and Sherlock had a good laugh at his brother's face as the spider crawled around the table as they talked. Even Gladstone seemed wary of the government man, as John had never seen him try to bite anyone else before. Mycroft had demanded to have "that awful beast" destroyed, only to be soundly rebuked by both Sherlock and John.
Sherlock walked into the sitting room one morning to find John tapping away at his blog. Gladstone was perched on his shoulder, almost as if he was watching the doctor type. Sherlock looked over John's shoulder and saw "The Detective's Pet" in large letter.
"Like the title?" John asked. Sherlock rolled his eyes, true to form.
Review! Do you like my interpretation of Gladstone?