Every strand of your hair is a library of your diet and DNA. A single hair can tell us the weight of the water you drank last month. We can tell whether you’re happy or sad. Your life is an open book, like wearing a black sweater when you live with a cat. You shed as much as your pet— your hair, dead skin cells, aerosols. Don’t even think about having an affair or committing a crime; your guilt will be written everywhere you’ve been where the forensic team can easily find it. If you’re guilty, the only thing that saves you is that nobody’s paying attention, except, of course, your guardian angel.