But like ordinary humans, there are good and bad people among the Tieflings, or rather, they are victims themselves. What is said to be their demonic traits is more like an eternal curse.
It is said that during the First and Second Ages, when Demon Lords and powerful Devils roamed the earth, humans were a very inconspicuous race.
Some people made contracts with these Lords from the underworld, willingly becoming their servants.
Even though these evil yet mighty beings were expelled from the prime material plane, they left an irreversible mark on these human servants, and their descendants would forever bear this curse.
Even if they intermarry with other races, humans, Dwarves, Elves, Halflings... their offspring might appear normal, but subsequent generations might still produce Tieflings.
So, a Tiefling who looks significantly different from ordinary humans might have parents who are considered "ordinary humans" in the eyes of others.
