The most common and most likely answer to this crossword clue is the 6 letter word TELLER
I've seen this crossword clue in The Sunday Telegraph
T
E
L
L
E
R
More clues leading to the result TELLER
Buddy explains!
The straight part
We know that "Banking official/one narrating story?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case banking official/one narrating story? = teller.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does TELLER mean?
TELLER noun- A device that provides bank customers with cash withdrawal and other services without the need for a human teller.
- A person who tells stories.
- A bank clerk who receives and pays out money.
- A person who counts the votes in an election.