office boys

Office boys are young male employees who perform routine tasks in an office, such as running errands, delivering messages, filing documents, and fetching coffee.

The term dates from an era when offices employed teenagers or young men for menial duties before they worked their way up to more responsible positions.

Though largely obsolete as a job title, it survives in figurative use to suggest someone doing low-level work or being treated as a subordinate: I didn't get an MBA to be treated like an office boy.