I did draw my character but she's inspired from an image search on Tieflings so I do not claim credit for this composition. I needed something to go on and I tried to make it my own.
I’d say she’s happy to meet you, but she’s not.
Her Great-Grandmother a descendant of Asmodeus made a bargain with the Infernal, granting power to her Lineage. Bri, born with soot black hair and dark horns, was shunned and deserted by all. Bri’s Mother was a horrible Sorceress who had intended to raise her for sacrifice in order to gain more power. An underling, human, smuggled the child away from her Mother. However, her rescuer was found out and killed. Fortunately for Bri, she was already safely hidden.
At the mercy of the forest the toddler was found by a pack of ravenous wolves. Using her magic unknowingly, she convinced this pack to protect and raise her. She had been content to live in the forest supported by her pack. However, as humanity grew and bred, they encroached on her forest home. Seeing the wolves, they were set upon by a mob, all of her wolves were murdered.
In a fit of rage and power, Bri killed some of the humans but not enough and she was forced to flee. She lived in hiding but out of need and desperation began interacting with the human world. Her magic is initially low because she went many years without training. Natural proficiency has given her the power to master some basic spells without guidance.
After wandering for a time she met a Warlock Miathus. He began her teaching and she honed her skills. They spent 2 years together and developed a relationship. They became comfortable in their home. Bri let her guard down. Accepting humans and trading with them. When plague struck the village and turned their human hearts- the humans looked for blame and decided they found it. They attacked Miathus and Bri, killing him as he protected his home and love. Bri was injured and this resulted in the miscarriage of her child. That dashed her hopes of ever having a child. Leaving her with a painful longing for a baby.
Her training incomplete and her hatred of humans growing, she feels total mistrust toward human kind. She is met with mistrust in return. She often wears a hood and carries her wizard staff. She hides in the shadows whenever possible. She is becoming a survivor. She is taking up odd jobs for money and seeks experience in the world to hone her craft.
She is not a particularly religious sort, she does understand the arcane bargains that can be made and that she is descended of the God Asmodeus. In the 15th century, all tieflings alive on Toril were apparently descended from Asmodeus and all had a similar devilish appearance. Prior to Asmodeus's ascension to godhod, the infernal blood could be diluted through intermarriage, but afterward, the union of a tiefling with another race always produced a tiefling child. She is aware of this fact and wanted a child with Miathus. He was willing to raise a Tiefling child. She also realized that many will not wish to copulate with her in that manner because who wants a Tiefling child?
This fits deeply into her hidden motivations.
Despite all, she is willing to trust a token few. Currently with a group of near-do-wells on a job that went awry she is hoping to find people she can trust and skills she can learn. She’s waiting for the right group and this might be it. However, she is torn- for there is a child among them and if opportunity strikes, will she steal away with the babe- or will she remain loyal to her comrades?