Louisa the Poisoner (Unabridged‪)‬

Raised in a swamp by a mad witch, poor Louisa grew up with one goal in mind: to marry a wealthy man, then inherit his lands and money by whatever means it takes. And Louisa may well succeed, for she is a stunning beauty with the manners of an angel. At last she sets off to make her fortune...and with the help of her vial of undetectable poison, she soon finds her first victim. A dazzlingly dark fantasy, as only Tanith Lee could write it!