Eve is a traveling merchant stationed in the port town of Lenos by the time Lawrence meets her. She's originally from the Kingdom Of Winfield, however, due to events in her past, she was forced to leave and start a new life as a merchant. As a merchant, she's extremely skilled and keen-eyed towards either profit or people. Hard to approach, few actually know that she's a woman. This is due to the fact that, for convenience, she wears heavy layers of cloth (usual to northern merchants) but also a long scarf that covers almost her entire face. When she's not wearing this outfit, she's known for extreme beauty and perfectly portrait a naive town lass.
She is in fact a fallen noble that was once sold as slave to another merchant after her family's fall. After going through horrible times, now she aims only profit, no matter the means necessary for it. In Lenos, she betrays Lawrence in their fur deal and flees to Kerube.
In the novels (volumes 8 and 9):
After getting caught in the Narwal mess in Kerube, her plan fails and she's nearly killed by Kieman. Lawrence saves her and later on she gives him more information on the wolf bones they're searching, along with her "true" noble name ...and a kiss. Holo obviously snaps at it. She aims to be the "prince merchant," a position atop all other merchants and trade companies, who directly negotiates with the nobility, can set deals between nations, and reports only to the king himself. Metaphorically, she is trying to live her life by herself. As a consequence from her past, she feels the need to set her own limits.