Another Racheal Lillis character that can be easily mistaken for Jessie.

Martina is the princess of Zoana and self proclaimed antagonist of Lina Inverse and party, while far from being a villain, she's more of an annoyance demanding attention, especially when Lina surrounds herself with cute male companions to flirt with; adding to her unique character, she's named after a famous female tennis player and made up a majin to worship called Zoamelgustar to try and play the villain but is too pathetic to do so and she only bothers Lina to begin with because Lina accidentally destroyed her kingdom in a misfire, but the fact that Lillis chose her Jessie voice for the role just makes her sympathetic enough that she makes for Lina's perfect foil, especially when you consider in OVAs that Naga the Serpent exists.
Lina having to deal with Martina on a regular basis gives the actual villain more weight when they get revealed.
Lina Inverse is so powerful that the only way to nerf her is surrounding her with friends and rivals too silly to be taken seriously but just competent enough that she can't do her job, Martina is the perfect example of this.