Chipmunk

 was a member of the A.F.A.D.. In the A.F.A.D. interrogation holotape, Rabbit accidentally mentions that his name is Mike.

Appearances
is only mentioned in Fallout 4.

Behind the scenes
A feral ghoul named Chipmunk can be spawned with the console. It may have been intended to be an enemy before being cut from the add-on.