Ned Blunt acts as a foil for the other male characters in the play, especially Willmore and Belvile. While Blunt superficially has several things in common with his friends—they are all exiled Cavaliers who seek to have fun at Carnival—he is the foolish and brutish antithesis to the other Englishmen. Willmore and Belvile also act as foils for each other, as their contrasting relationships with women radically differentiate their characterization.
Blunt functions as a foil for Willmore and Belvile in different ways. Willmore is a reckless and promiscuous rake, which are qualities one can discern in Blunt. However, Willmore is also clever and charming, winning over both Angelica and Hellena despite his vulgarity and inconstancy. Blunt is vulgar, but he is not at all clever or charming. His brutishness accentuates Willmore's prowess.
Belvile is not vulgar, like his friends Willmore and Blunt are. He is a true gentleman, steered at all times by his devotion to Florinda and desire to do right by her. Belvile's constancy operates in stark contrast to Willmore's characterization, as the character is constantly searching for new women to seduce. Whereas Belvile is paired up with a single woman from the beginning to the end of the play, Willmore is paired up with both Hellena and Angelica—as well as any woman he is intrigued by in passing. Blunt is not exactly paired up with any woman, but believes he has found love with Lucetta, who takes advantage of him and literally steals the clothes off his back.
Blunt and Willmore are not only Belvile's foils, they also obstruct his efforts to be reunited with Florinda—both of his friends even attempt to rape her. The relationship that these three men have to Florinda encapsulate their contrasting characterization: Belvile is in love with her and wants to marry her, Willmore tries to sexually assault her because he is sure she has tried to seduce him, and Blunt tries to sexually assault her because he wants to take revenge on all women.