The most common and most likely answer to this crossword clue is the 7 letter word FANCIER
I've seen this crossword clue in The Daily Telegraph
F
A
N
C
I
E
R
Buddy explains!

The straight part
We know that "Devotee" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case devotee = fancier.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 FANCIER mean?
FANCIER noun- One who fancies; a person with a special interest, attraction or liking for something. An aficionado.
- A person who breeds or grows a particular animal or plant for points of excellence.
- One who fancies or imagines.
- Decorative.
- Of a superior grade.
- Executed with skill.
- Unnecessarily complicated.
- Extravagant; above real value.