Yolanda Haymer

Yolanda Haymer is a level 70 human reagent vendor located at the Amberpine Lodge in the Grizzly Hills.

Trivia
This might also be a reference to one of the characters on the show Firefly, in the episode "Trash". Standing next to her is an NPC named Saffron Reynolds - this is more likely a reference to the episode "Our Mrs Reynolds". Probably a fun easter egg introduced by one of the designers.