The most common and most likely answer to this crossword clue is the 8 plus 7 letter word TAIL-END CHARLIE
I've seen this crossword clue in The Guardian
T
A
I
L
-
E
N
D
C
H
A
R
L
I
E
Buddy explains!
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.