Calling your friend the alter ego "Charlie Baker" is man code for calling him a cock block. (thus the initials C.B.) It is to be used when one man is with a girl and his buddy begins to cock block him. If he doesn't want to straight up say his friend is being a cock block right in front of the target he will call him Charlie Baker.
"Hey man what are you guys doing tonight? Can I get in the car?"
"C'mon Charlie Baker! Someone else will give you a ride."