1) The very pit bottom of the relationship hierarchy where a girl considering a guy to be a friend would be consider an insult to her well being.
2) A female that befriends a guy and misleads him into thinking that they are friends but her ulterior motive is that she is using him for academics.
Zak: "I think I am in the friends zone with Emily"
Vladmir: "Nah, you are only in the tool zone.."
Zak: "Why do you say that"
Vladmir:" She only comes to you for Calculus problem sets"