In hindsight the closed doors between the living room and the kitchen should have been his first sign that something unpleasant involving one of Sherlock's experiments is about to happen. But John who is simply happy that Sarah had let him go before the end of his shift (since most of their patients seem to enjoy the summer day) opens the door and is immediately greeted with a terrible noise and a flush of a reddish fluid. A reddish fluid that has not only his entire front covered but also the complete kitchen walls and Sherlock who astonishingly is clothed in a lab coat with protective goggles on.
Much, much later when he is clean and calm again he would be able to reconstruct the exact timeline of another catastrophe that happened to the flat. Namely the unlikely coincidence of him opening the door while Sherlock pushed the start button of the blender which contained his self-mixed blood substitute. But right now he is pretty much frozen to the spot. When he gains control over his limbs, he wipes the fluid from his face just in time to see Sherlock stop the blender and grin in delight before he starts his victory dance that is usually reserved for promising murder cases.
"Brilliant. I knew it." John hears his lover exclaim before he spots John in the doorway.
"Oh John, you're home early. Did you see it? It's great, isn't it?"
Sherlock's annoying habit of involving him in a dialogue where essential parts are missing is the final piece that brings the doctor to life again.
"Great? Are you fucking kidding me? You destroyed the kitchen? And the living room for one of your insane experiments?"
Too used to John's temper, Sherlock merely corrected: "Actually the living room was your fault. Why did you open the door?"
"Why did I open the door? Oh, excuse me when I try to access my own kitchen and look for my partner. What the hell were you doing?"
Sherlock's good mood vanishes.
"Proving a point. I don't expect you to understand."
The hint of arrogance with the implications on his intellect are nothing new, however they still get to John sometimes.
"Oh yes, sorry, I forgot I'm an idiot. Well, the idiot will now shower and leave the cleaning up to you."
John stomps in the bathroom, getting rid of his clothes with angry movements. The shower doesn't lighten his mood, but getting out of the flat and the presence of this madman does the trick. After all it is still an unusual sunny afternoon in London and watching other people enjoying their day leaves him contemplating a bit on his life choices. Not in a way that means he will actually change something, but sometimes he wonders what was so wrong with 'Nothing happens to me'.
He isn't surprised when Sherlock sits down beside him, but he eyes the two ice cones warily.
"There is nothing wrong with them!", the detective huffs.
"I've been already subject to one of your experiments today, forgive me if I worry a bit."
"Your involvement was an accident, I didn't expect you to be home so early. Now take your cone."
John wants to say something but in the end he just silently accepts it. They are eating slowly, settling in some uneasy quietness, finally broken by John.
"Okay, tell me about it!"
"I don't think it is suited for the occasion."
The doctor can't resist the disbelieving look.
"That has never stopped you before!"
The answering grin is a bit apologetic until it turns in a stream of words. He is right, talking about a murderous butcher, human blood in a blender and splash marks in an industrial kitchen isn't the best conversation he has ever had over an ice cream cone. But hearing the assurance that Sherlock has hired professionals to clean their flat while they are sitting in the sunshine makes it better. Good enough to take Sherlock's hand and press a light kiss on his knuckles.
"Thank you for the ice cream."
