If I could write, this is what I'd be writing right now:
Jim (the fanboy, ever since Sherlock had noticed that there was something off about Carl Powers's death) organizing crimes not only only to entertain himself but also to entertain Sherlock (it's all fun and games - even more so when someone loses an eye :oD). And occasionally - with his super blend-in skills - secretly hanging out near Sherlock. That's what obsessive fans DO!