Spenser employs dramatic irony during Britomart’s stay in the house of Malecasta. Though the reader knows that Britomart is a female knight, her knight’s armor has concealed her body and Malecasta has falsely assumed that Britomart is a male. In a deeply ironic scene, the “Lady of Delight” attempts to court Britomart: 

Whom when the Lady saw so faire a wight, 
All ignoraunt of her contrary sex, 
(For she her weend a fresh and lusty knight)
She greatly gan enamoured to wex, 
And with vaine thoughts her falsed fancy vex: 
Her fickle hart concerned hasty fire, 
Like sparkes of fire, which fall in sclender flex, 
That shortly brent into extreme desire,
And ransackt all her veines with passion entire.

Malecasta is “ignouraunt” of the “contrary sex” of Britomart, whom she believes to be a “fresh and lusty knight.” Britomart is not only, as Spenser acknowledges, a female knight, but also the Knight of Chastity, leading her to butt heads repeatedly with the "wanton" Malecasta. In a simile, Spenser further describes Malecasta’s growing attraction to Britomart, which “like sparkes of fire” has set  “hasty fire” to her “fickle hart,” a fire which has spread through her “veines” and consumed her entirely. Malecasta’s subsequent attempts to seduce the female knight present the first of many challenges to the Knight of Chastity throughout Book III.