"Car Saleswoman" is not an official name. It may have been referenced by ids5621 as such, but has not been officially named. Alternatively, it may be a name popular among fans, but has no official basis.
The Car Saleswoman is an unnamed saleswoman who sells cars that appears in Jevik? Pt 3, being distracted by Pyrex while he and Jevik stole an MVT she was selling.
Nothing is really known about her other than that she sold cars. During Jevik? Pt 3, Pyrex approaches her to distract her while Jevik stole one of the MVTs she was selling by planning to flirt with her. While she initially seemed okay with talking to him, after seeing what he looked like, she ran away in terror. Pyrex assumed she was already seeing someone.