Jergos' potions range from greater to extreme quality. His admirer, Moira, can be found at his stall flirting with him. Unfortunately for them both, her husband Connor is sitting on a bench nearby. Regardless, he enjoys the back and forth, and is both flattered and slightly frightened by her affection.
Jergos can be mindread for 15000 exp to lower his prices by 25%, revealing: "My business will go down the drain if more customers don't come. Perhaps I should take the edge off my prices to entice them."
Location of Jergos ("M" on map - click image to enlarge):