Sometimes, (usually on Wednesdays) before he sets his long feet against the planks of his bedroom floor, he thinks about it, filling in another card and placing it reverently back into the file in his mind's cabinet. The drawer is getting heavier by the day. He usually smiles.
Sometimes he's dull.
Shoot her with John's gun. Just once. In the head.
Sometimes he's thoughtful.
At a fitting, smother her with an entire skeen of that hideous fabric she loves so much. Ivory. How telling.
Sometimes he's terribly efficient.
Air embolism. It's quick.
Sometimes he's elaborate.
Wait for a sunny day. Hire a hot air balloon. When she's dithering about observing the sheep, gently lift her up and over and, depending on how and where she lands, dehydration may factor in before the damage of the blunt-force trauma.
Sometimes he's scientific.
At the surgery, use a clean scalpel to open both carotid arteries exactly 2cm and calculate the coagulation rates of the right one versus the left. It shouldn't take long; she's smaller than average.
Sometimes he's aggressive.
Any blunt object. Until her skull cracks.
But sometimes he gives up.
Have Mycroft relocate them and never tell me where. Ever.
Just stay in bed.