The CDN account known as WatchingCharon has been linked to one of Cerberus' cells on the Citadel. While only one member (the eponymous Charon) was known to use the account to post, rest assured that the rest of the cell used it to observe the forum's goings-on.
The Cerberus agent known only as Charon was a member of the terrorist group's public relations and politics division. A Scott City native (Terra Nova), Charon graduated with a double first in Alliance Law and Politics from the University of Terra Nova before he was recruited to Cerberus.
While he was loyal to the cause, professing a desire for humanity's independence and security, his superiors felt that his dedication was half-hearted at best: Useful for his role in lobbying the Alliance Parliament and co-ordinating propaganda efforts, but ultimately unhelpful for the organisation's future plans. With that in mind, his cell commanders forced him to murder an asari during a high-pressure operation, later describing it as a 'test'.
Under constant urging from his commanding officer, Charon killed the asari and framed a high-level turian diplomat for her murder. Horrified at what he'd done, Charon briefly escaped from his cell in an attempt to escape both the Citadel and the terrorist organisation, but was recaptured by Operative Isabella.
Safely back in Cerberus hands, Charon was 'talked around' to the cause. He underwent extensive psychological conditioning before returning to the Citadel.
Aside from viewing aliens as being the complete antithesis of humanity (and all the moral consequences that follow that train of thought), Charon enjoyed association football, tennis, salarian cuisine and contemporary volus music.
Operative Isabella Mirice, also known as Belle Rosales, was the de facto leader of Charon's cell. A highly-ranked Internal Affairs Operative, Isabella's role was not only to run the cell but to keep other Cerberus operatives in line.
Isabella led a complicated tripartite life. Under the name of Belle Rosales, she was an acclaimed holographer in her own right - her coverage of the Laval civil war was nominated for the prestigious Leung Awards - which acted as one of her cover identities for both Cerberus and the Alliance Intelligence Service.
In her guise as an AIS agent, Isabella was in a prime position to lay down convincing misinformation and to help Cerberus stay aware of exactly what the Alliance was up to.