The age of sexual consent is 16 but you must be 18 to be tattooed, despite the possible consequences of sex being arguably much greater than having a picture on your body that you may regret in a few years time. Tattoos can feel absolutely necessary to people, covering scars or "imperfections" is a big deal, self inflicted scars especially. I believe that people shouldn't have to wait so long to conceal those sorts of things and make changes to their bodies.