The weapon that I built is invincible. Against it, Lucy is nothing more than a little girl.
–The Operatives, not remembering that pride cometh before the fall
Called the Operatives here, these agents go unnamed in the series. They are two intelligence agents working for Saseba.
In the manga
These operatives are assigned to the First Escort Fleet and given authority over the Fleet Commander himself, while the fleet transported its secret cargo of Vector Attack Craft to attack the stronghold of Chief Kakuzawa at the Diclonius Research Institute. Fanatically Anti-Diclonius (The lead operative almost proudly spoke of the euthanizing of his Diclonius daughter and his own subsequent sterilization), they were also arrogant towards the commander and crew and dismissive of concerns about their safety during the transit, even summarily executing an officer who refused their orders. As the ships in the fleet were rapidly lost, the crews' complaints were regularly overridden. At one point, the pair bound and gagged the Fleet Commander and took direct control over the flagship. During an initial raid, the lead operative recovered Arakawa, whom he tasked for her role in knowingly aiding Kakuzawa's agenda. Despite his doubts about her and her doubts that the vector attack crafts could take on Lucy, he sent her back to the island to recover the only known samples of the Anti-Diclonius Birth Vaccine. It had been the intervention of another, far more subtle, Saseba operative, the Agent, that had gotten her off the island initially. The second operative was mutinied against by the crew, restoring their Commander just before Lucy's rage on behalf of Kouta destroyed the flagship. The lead operative had the dubious distinction of leading the last-ever military assault on the dying Lucy, with no more success than any of his many predecessors, his righteous rage coming just at the time when Lucy's inner voice was in control. To be certain, since he also threatened Kouta, it can reasonably be said that he probably wouldn't have done well with Lucy. The pair were strongly devoted, if again not fanatically, Anti-Diclonius, viewing any and all measures to stop them as being well within bounds.