This page reveals a lot of the plot. If you have not read the entire series I understand that Ruby Redfort series are pretty long but your patience will be payed off in the end :).
Buzz was thought to stand for Brenda Ulla Zane as revealed in the final book, Blink & You Die, but was in truth an acronym for Baker (Bradley), Ugerlimb (Loveday Byrd aka LB) and Zachery (Art Hitchen aka Hitch).Her real name is Casey Morgan.
It is also revealed that she had been attempting to kill Ruby from the start, so that she could get hold of the code that lay in her eyes which would decode the 8 Key's tag. She had attempted to murder Ruby even before she (Ruby) joined Spectrum. She attempted this by trying to lure Ruby with a yellow balloon and a puzzle at the back of a cereal box. She was unsuccessful as Ruby was only interested in the tag of the balloon and also because her father forgot to post the solved puzzle.
Throughout all of the books, she has been working undercover as Spectrum 8's receptionist- convenient as it allowed her to intervene with important messages.
Other Character's Opinion Edit
Ruby often likens Buzz to a mushroom- referring to Buzz's "fashion sense" and the way the table is positioned around her. She (Ruby) attempts to make conversation with Buzz occasionally. In the final book, when Ruby is suspicious that Hitch is Casey Morgan, Buzz pretends to agree with Ruby and offers help which Ruby accepts.
It is impressed upon that LB thought that Buzz was an efficient receptionist as she was not "chatty"