Gregoire, also known as Gregor, was a member of the three-man Simeon Reconaissance Squad known as the Flea Team.
Following Kafka's destruction at the hands of Adam Blade, the Flea Team was at risk of being disbanded, having lost its leader and only offensive type Needless. Therefore, Zamusa and Gregoire resolved to capture Disk, the Resistance's information broker, Disk, while Blade and Teruyama were away. However, when Gregoire used her Fragment to "listen in" on Cruz, Disk, and Gido, she misinterpreted their conversation for something....indecent.
Zamusa and Gregoire, remembering Cruz's blood relation to Aruka Schild, began to overestimate his powers. Ultimately, they were both annihilated by Disk's finishing move: Destroy Evolution (even though Disk wasn't even aware of their presence).
St. Rose Academy Arc
Although Gregoire was thought to be "buried alive" as punishment for failing her mission, she makes a brief appearance in Chapter 56 of the manga to inquire about Arclight's condition and to give a status report about the extraction of data from the Resistance chip.
Powers and Abilities
Fragment: Hell's Ear - grants her a greatly enhanced aural perception. She can listen in on any conversation, even if they are on the other side of thick concrete walls. However, the downside to this ability leads the user to misinterpret whatever they hear.