A security officer for the Flamin' Hot Cheezos company, Benchee is the head of security at the Cheezos Factory. He is extremely dedicated to his job, a drive stemming from when he was a child, and someone stole a bag of Cheezos from him.
When Zim plots to blow up the Cheezos factory to spread cheese dust into the atmosphere and make Earth uninhabitable for humanity, he kicks the plot off by sending an email allegedly from the Cheezos home office ordering that a hyper-singularity power plant be added to the factory. Benchee doesn't see the necessity of such an addition, but as the email seems legitimate, he allows Engineer Scientist (Zim) and his assistant (GIR) access to the factory.
However, Benchee becomes suspicious when he notes that their personnel files have no mention of an Engineer Scientist, suspicions that grow due to damages caused by GIR, who has begun malfunctioning and trying to kill Zim. This eventually leads Benchee to rightfully believe that Zim is attempting to sabotage the factory. He takes Zim prisoner and attempts to interrogate him, only for GIR to attack him and his guards.
Zim uses this to convince Benchee that GIR is the threat, not him, and thus Benchee releases him. Zim then tells Benchee that GIR is afraid of Cheezo dust, knowing perfectly well that he isn't, for seemingly no other reason than for him to attack GIR and lose. This results in Benchee being launched out of the factory.
After Zim has stopped GIR's rampage and is leaving, Benchee comes up to thank him for stopping the power plant from melting down from damage caused by GIR. However, Zim didn't actually fix that damage, and the plant indeeds melt down; Benchee is apparently killed when this happens, as his glasses and hat are seen floating above the resulting crater.