Госпожа Чейн is Horadric's wife, the innkeeper of The Dead Horse.
She is one of three NPCs (the other two being Horadric and Vagner) present at the tavern on all of the six days irrespective of day/night.
After you brought back Ms. Charm the bad news about her Necklace, she wants Miss Chain's Perfume. In order to get it from her, you have to deliver a Basket of food to her sister Clotho, and bring back 12x Frog as ingredients for creating more Perfume. For this you'll recieve a total of 20 and you can get the Perfume from her.
She sells four cookery technology recipes.