Eda is the rival/friend of the main protagonist Revy in the series, Black Lagoon.
Eda is a woman who appears to be in her late 20's - 30s, has blond hair, blue eyes, and wears angular pink sunglasses even with her nun's habit and is often seen either chewing gum or smoking. When she isn't in her nun's habit she is wears a miniskirt and a tight tank top that shows off her well endowed body.
She is first introduced in Episode 7 "Calm Down, Two Men", when Rock and Revy try to buy weapons from the Rip-Off Church and almost ends in a shootout when Revy's undiplomatic methods force her and Eda into a standoff, but Rock finishes the negotiations and the Church lets them go. She is seen again in other episodes where it is shown that Eda is friends with Revy, but they still violently confront each other as they share the same hotheaded personality. She has taken a liking to Rock during the "Second Barrage" episodes, and makes fun of Revy by playing on her suppressed romantic feelings for him by threatening to take Rock for herself and excessively flirting with him.
In "Roberta's Blood Trail", when the NSA's Grey Fox team instigates an operation in Roanapur without consulting her division, she is tasked with tracking down Grey Fox, the same foe Roberta is hunting, and providing intelligence about their mission to Mr. Chang, but warns him about his actions. She also helps Rock out with his plan to get Grey Fox out of Roanapur as well as helping Roberta follow Grey Fox to Laos; though when Rock suspects that she might not be who she says she is, she warns him to not go further for his own safety. She is last seen telephoning her division head in Langley regarding taking over Grey Fox's mission.
Eda's preferred firearm is a Glock 17L (as seen in manga chapter 41), which she wields proficiently, despite Revy's claims that she is a "second-rate gunman".