Paying Attention (Johnlock)

Sherlock and John are sitting at the kitchen table, Sherlock engrossed in his microscope. John is borderline politely trying to get Sherlock's attention. Nothing seems to be working, not even throwing bits of food at him, so John 'accidentally' drops something under the table. While under there, John tries to see if some sexytimes will knock Sherlock out of his musings. Cue Sherlock trying as hard as he can to focus on what's under his microscope rather than what John's doing to him under the table.