Often misunderstood in more rural communities, but well-respected in urban settings, Tieflings are the result of humanoids, mostly Humans, mingling with fiends from the lower planes a long time ago. This however doesn't truly affect their morality or personality, especially since none of this is their fault... they're normal people, just with a smidge of fiend in them... even if quite a few people may be wary of them. Many people may get over this prejudice after getting known to a Tiefling, but some may never get over it... But if you befriend a Tiefling, you may find a friend for life.
Most Tieflings are descended from devils, but more commonly only a few hundred years ago, and slowly once more in more recent times, Tieflings descended from other fiends like Yugoloths and Demons can be found.