Cognitive and cultural embeddedness: combining institutional economics and economic sociology
According to this, pederasty is sexual relations between two males, especially when one of them is a minor. Other definitions, like the one that JSBangs found, differ slightly. But otherwise, I think you answered the question yourself: pedophile refers to the attraction, while pederasty refers to the act itself.
Dermal piercing, also known as microdermal piercing, is a form of body piercing where the dermis, i.e., the layer of skin underneath the epidermis, the outer layer of skin, is punctured or cut in order to place body jewelry.