Sherlock had found nicotine patches in a recess of Molly's house, when she was out on a job, and although she was frustrated that he had been looking through her personal possessions she agreed to let him use them. She wouldn't tell him why she had them- it helped her to think and sort the various intelligence she had obtained into categories as she couldn't write any of it down, obviously -because she had copied the technique from the consulting detective. Molly should have known it was futile to keep any secrets from her flatmate because he could deduce the details of the secret in a matter of seconds, although he had learned not to say anything when he did it to her. He still did it, of course. If he stopped, he would loose his powers of deduction altogether. He still didn't know how he missed the fact that she had a whole other life, and that the awkward, quiet Molly he thought he knew was a complete facade, but he could work out some details of her various jobs- the approximate location, some details of her employers. Molly didn't like it because he already knew more about her and her secret life than he should, bu she supposed it was her fault for letting him into it. The only other person she had ever let in was Jim.