A good one

Beautiful and very well-written.

Beautiful and heartfelt little piece. Loved it, especially Sherlock's motivations for using- they seem so real.

There were a couple instances where a comma would improve the meaning. "John sat down next to Sherlock, placing..." and "head to his shoulder, carding...". I also thought there were a couple of instances of "word cruft"- words that didn't add anything to the meaning and could get in the way. "Actually, practically all..." this could probably be parsed down to "Sherlock was shaking. John recognised the symptoms." "Right now it didn't really..." That entire sentence doesn't strictly need to be there. "less fragile, less tempted" might be strong if you chose one or the other. "Not now" could also probably go.

But your mileage may vary. Thanks for writing x