Tiefling

Tieflings are not a true race in themselves, but rather a form of planetouched, born out of happenstance. For seemingly no reason, children of ordinary parents will sometimes enter the world with horned heads, fiendish visages or whiplike tails, among other anomalies.
It is widely believed that tieflings were brought to the world as a result of some ancient fiendish pact. Whether true or not, many tieflings face prejudice for such beliefs, which are only empowered by the often strange and unsettling looks of these misunderstood people. The condition has been documented in all mortal races, though some of them view it as a curse to be stamped out.
Tieflings are similar in many ways to the aasimar, whose heritage is celestial in nature.