How long does weed stay in a skinny person's system

THC is stored in fat. That being said, even if you are a skinny person there are other factors that could affect how the test would turn out. It depends on how much water you drink, what kind of test you take for the weed and how much weed you smoke. There is no set answer. It could be a week or 10 days if you aren't a steady user of pot.