The most common and most likely answer to this crossword clue is the 8 letter word BUMFLUFF
I've seen this crossword clue in The Guardian
B
U
M
F
L
U
F
F
More clues leading to the result BUMFLUFF
Buddy explains!
The straight part
We know that "that’s faced by pubertal boys" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case that’s faced by pubertal boys = bumfluff.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 BUMFLUFF mean?
BUMFLUFF noun- The first, sparse beard growth of an adolescent.