It’s because he wishes Neville would have been the Chosen One instead of Harry (and by extension, would have saved Lily’s life).
WHOA


CRYING
#this is how it’ll go down #sherlock outside 221b at two in the morning #with a stereo blasting this song#and john will come downstairs and beat the shit out of him #because um rude it’s two in the morning be a little more courteous #also you’ve been dead for three years you bastard #and they’ll communicate solely through 80s power ballads for about a week #until mrs. hudson threatens to kick them out #then they talk it out and make out #i mean make up yes make up……. #and every now and again #sherlock will walk by john and whisper ‘baby don’t hurt me’ #and john will throw things at him #yes happy ending #wow i need to stop
THOSE TAGS
“BABY DON’T HURT ME” AND JOHN WILL THROW THINGS AT HIM
THANK YOU FOR THE MENTAL-IMAGE OF SHERLOCK STANDING ON THE DOORSTEP OF 221B AND FLUMMOXING JOHN OUT OF HIS RAGE BY DOING BIG-FISH/LITTLE-FISH/CARD-BOARD-BOX AT HIM.