Five times Sherlock came in his pants...and the one time he didn’t
It would only be fair to mention that he was twelve and still reeling from the cacophony of hormones that seemed to have made every single nerve ending hypersensitive and had also seen fit to give him bionic vision which zoomed in unerringly on any exposed patch of skin within a five mile radius. Didn’t matter if the owner of said skin was bundled in fifteen layers of clothing, his overactive imagination helpfully supplied the bits unseen in lurid detail.
It was completely unfair that the seat was still warm from the old lady who had recently vacated it and whilst he was trying to get himself under control the coach had gone over an unfeasibly large bump in the road and, well, there you have it.
The next few hours were extremely uncomfortable; he sat curled in on himself with his crotch drying cold and stiff but the rush of sensation previously read about but never experienced had been so unexpected, so thrilling he almost gave it another go under cover of his entomology textbook. The thing that stopped him, however, was the image of Mycroft’s smug, appraising expression in the car on the way home. Once he could get away with, twice would be more than mere accident and Mycroft would just know.