Gallow is the vintner who helped Lord Kandur Hosidius, the current lord of the Hosidius House, to develop the Vinery for grape farming. She will look after a player's vine patch for free.
Her name is short for 'Gallows'. She claims that when she was young, a boy made "some improper suggestions" to her, and she choked him and held him in the air until he "learnt some manners".
Gallow is the solution to the medium anagram clue: LOW LAG. The challenge scroll answer is 12.