Wendy

"Oooh, too slow! I think I'll call you molasses."

- Wendy

Wendy is a hyperactive, enthusiastic teenage girl, voiced by Brenda Song, and a possible rival to Candace Flynn for Jeremy's affections, who first or only appears in "Unfair Science Fair".

In the episode, when Jeremy suggests to Candace that she take the job opening at Mr. Slushy Burger so they can work side-by-side, Wendy suddenly steps in, offering to apply for the job, to Candace's chagrin. But since there's only one opening, the manager suggests they compete to see who is a better choice for the job. For their first task, the two of them are supposed to dress some hot dogs with ketchup and mustard. But Candace and Wendy end up turning their contest into a food fight with both of them throwing the food dressing at each other, which results in both of them wasting all the hot dogs ingredients and losing the job opening.

Interestingly, at the beginning of "Unfair Science Fair Redux (Another Story)", Wendy is among the people Candace tries to call, asking to hang out; Candace mentions there that they shared a seat on the bus to the planetarium.

Wendy is possibly named in reference to the Disney Channel Original Movie Wendy Wu: Homecoming Warrior, of which Brenda Song starred as the titular character.

Candace Flynn
Candace was her opponent for the job position. But, as mentioned above, they did once sit together on the ride to the planetarium. Both are sort of having a 50-50 relationship with each other as friends.

Jeremy Johnson
Possibly, Wendy may have a crush on Jeremy as well as Candace does. This may be the reason she took the job.