Sometime during of Gladstone's first month at 221B, Sherlock tales it upon himself to train their young cat.
"Bengals are both very powerful and very intelligent," he tells John from the sofa one evening, dangling a feather-adorned fishing rod toy over Gladstone's fuzzy little head. Sherlock has been lounging around in his pyjamas and dressing gown all day long, opting to, for the moment, obsess over the cat rather than sulk over the lack of an interesting case. Gladstone is putting up quite the fight, batting savagely at the cluster of rainbow colored feathers. Occasionally he lands a successful bite and Sherlock lifts him off the rug for a few seconds, his wiry kitten's body twisting and tugging, until he is lowered back down to Earth to begin the struggle all over again. "It only makes sense that he needs to be stimulated, not just physically, but mentally as well."
John chuckles. "That right?" He doesn't look up from his laptop's keyboard, head bent to peck away at the keys. He is sitting across from Sherlock in his armchair, attempting to chronicle a case from last month that he hasn't yet gotten to post. It takes him a few seconds to register the lack of reply; he can practically feel Sherlock's eyes settle on him, beseeching him to look up.
"You don't think I can do it." John had long ago learned to recognize that certain intonation in Sherlock's voice. It meant he smelled a challenge and was ready to rise up to it.
"No, that's not what I meant." John shakes his head and looks back to his blog. "If living here has taught me one thing, it's never to underestimate you when you've set your mind to something. It's just." He bites his lip, searching for the words. "Cats can be very stubborn, Sherlock."
"Cats can be trained, John. It's not unheard of."
"I know. But it's going to be very hard to convince a cat to do something he isn't motivated to do. Gladstone's not a dog, and I know for a fact your patience is not infinite."
"John, I doubt even you could have failed to notice just how food-motivated our cat is. That could prove to be a great boon in training him. Surely you can't have forgotten the lengths to which he went for your bacon sandwich last Monday—"
"No, I certainly haven't," John mutters into his keyboard. He vividly remembers Gladstone's death defying leap across two countertops and a kitchen sink towards the aforementioned sandwich, only to face plant straight into the edge of the table. John had let out a slightly less than manly yelp and proceeded to fret over Gladstone for the remainder of the afternoon, much to Sherlock's amusement. The kitten turned out to be just fine, if resigned to wait until he was of a more impressive size to attempt a stunt of that magnitude again.
"I intend to use that advantage to motivate him into doing my bidding." Sherlock seems unaware as to just how foreboding that sounded. "If he is left without stimulation, he might take to tearing apart the furniture or developing behavioral problems—"
"Yes, because god knows it's hard enough work keeping you from doing just that."
Sherlock promptly shuts his mouth with a snap of teeth and gives John a haughty, sulky glare. With a huff, he tosses the plastic handle of the feathery toy to the ground and snatches up Gladstone to stomp off to his room. Gladstone is still attached to the toy by the feathered bit and it bounces against Sherlock's arm as he stomps away.
"Hey!" John calls from his chair. "Where do you think you're going? You got him last night, tonight's my turn!"
"Good night, John." Sherlock's snappish parting remark is punctuated by the sharp slam of his door.
"Oh, hell!" John closes his laptop, accepting the fact that he would not be posting the details of a bank-robbery-turned-cannibalism-scare and hefts himself out of his chair. In nine strides he is at Sherlock's bedroom door.
He knocks once. "Sherlock."
There is no reply.
"Sherlock, it's barely nine o' clock, I know you're not going to bed."
"Leave my door at once."
"What—no! Sherlock, you're being a child!"
"I am not."
"For god's sakes, you're holding my cat hostage in your room—"
"Our c—the cat! You're holding the cat hostage! Okay, you know what," John grasps the doorknob and braces himself. "I'm going to count to four, and when I get to four you are going to open this door and give Gladstone to me or I am going to come in myself and make you. Do you understand?"
He takes a deep breath. "One."
There is a rustling on the other side of the door, which John assumes is Sherlock flopping about on his unmade bed. Probably trying to hide Gladstone.
Still no evidence of a pending peace offering. John's hand tightens around the doorknob in preparation of turning it.
John swings the door wide, flinching internally at the sound if it hitting the wall but keeping the concern out of his face so he appears as intimidating as he can in an argument over a kitten. Sherlock's head whips around to face him. He is perched on his bed and his eyes are widened in what John is oddly satisfied to find is genuine surprise. He can see Sherlock tense on top of the duvet in anticipation of an attack.
"Where is he, Sherlock?"
"I'm not going to tell you."
"All right then."
John launches himself at the world's only consulting detective. In a flash, he's looming over Sherlock on the bed. Sherlock begins to squirm, letting loose a badly aimed kick to John's belly. John can't help the poorly contained grin on his face as he moves to kneel on one of Sherlock's thighs to prevent future kicks in his direction. Sherlock attempts wrap his other leg around the back of John's kneecap in order to incapacitate him, but it doesn't exactly work out as planned. All that manages to accomplish is his further entrapment in providing opportunity for John to grab at his wrists.
"John Watson!" he nearly shrieks from behind clenched teeth. His face is turning pink with the exertion and the close proximity. The smell of John's aftershave is everywhere. He yanks his arms back and forth with the intention of dislodging John's grip on his wrists. Sherlock is completely competent in hand-to-hand combat, but John had caught him off guard and he's getting tangled in his dressing gown, not to mention the fact that John was a decorated soldier.
"Where's Gladstone?" John's voice is laced with a breathy laugh that does nothing to combat the flush in Sherlock's cheeks. He can't help it; he knows he's too old to be wrestling like a rowdy teenager with his flat mate on said flat mate's bed, but it's fun to watch him squirm. "I'll let you go if you tell me where you hid him."
Sherlock gives a completely masculine little shout of surprise as he is flipped over on his stomach. John pulls his arm behind his back and puts his weight on it, just enough to restrain but not enough to cause any real pain. Sherlock kicks his legs to try and catch John in the back with his heels, but the slippery bastard is just out of reach. The side of his face is being shoved into his duvet and he's starting to drool all over it.
"John!" he groans, giving one more full body squirm and feeling John's ribcage expand over his back.
There is a familiar reverberating meow and John's head snaps up to survey the room. Sherlock gives a half-hearted sob against his now soggy duvet. "P-pocket!" he croaks. "Other dressing gown!"
John stands from the bed to investigate and Sherlock sighs with relief. Inhaling freely, without the dead weight of and ex-army doctor, he turns over on his back to stare at his ceiling.
"There," John murmurs, extracting Gladstone from the pocket of Sherlock's burgundy dressing gown, which was hanging from the hook on his closet door. "That wasn't so hard, was it?"
As soon as Sherlock moves to launch himself from the bed, John darts out the door with Gladstone cradled in his arms. He's not jaded; he may have just bested Sherlock in a close proximity tussle, but he knows Sherlock can outrun him any day of the week. He loses him at the foot of the stairs leading up to his room. John closes the door behind him and leans against it. Gladstone jumps from his arms and runs to re-explore the closet.
"Don't think for one second that I will let this indignity go unpunished, John!" Sherlock calls up to him. "You'll have to come out to brush your teeth and I will be waiting."
Gladstone's training begins the very next day. Sherlock, after a few hours of reading internet articles, goes out and buys a clicker and numerous pouches of fish-themed treats and begins immediately upon returning home.
In fifteen minutes, he has taught Gladstone to sit.
"Oh, fuck me." John glares in disbelief as Sherlock clicks the clicker and feeds Gladstone another treat.
"He will learn to associate the sound of the clicker with receiving a treat, and a reward in the form will no longer be necessary. Eventually he'll just heed the command without the aid of the clicker."
"Yes, yes, right." John goes back to reading his paper.
Next is breaking Gladstone's unsettling counter surfing habit.
Sherlock purchases several sheets of sticky fly-paper and a few cheap place mats. He applies the fly-paper to the mats and leaves them on the countertops. When Gladstone jumps up to help John prepare his eggs and toast the next morning, his little feet stick. He begins to cry and looks at John with wide, shining eyes in a desperate plea for help. John, chuckling to himself, pulls the poor thing free of the sticky trap and deposits him on the floor.
"Won't be doing that again anytime soon, will you?" he murmurs, watching as Gladstone scampers off to climb into his cat tree. To reinforce the proper use of a climbing surface, Sherlock presses the clicker and feeds him a treat.
A week later, John sighs as he watches Sherlock, bent in half so that his back is parallel to the floor, command Gladstone to jump from the top story of his cat tree and onto his flattened shoulder blades.
"My god." John shakes his head. Sherlock looks over and flashes him a smug smile. With a familiar click, he reaches over to feed Gladstone a tuna-shaped treat. "I'm speechless," John murmurs. "Speechless. That's amazing."
Sherlock grabs up Gladstone from his back and puts him down on the floor. "It isn't difficult, John. Combined with his intelligence, Gladstone's surprising willingness to please makes him very amenable to instruction. Not to mention the eagerness for praise in the form of food." He flops down next to John on the couch, sitting cross-legged in his suit trousers and with his Italian shoes still on his feet. "What next, do you think? Shall I start with the hoops?"
"I think you need a bloody case, Sherlock, and soon."