The most common and most likely answer to this crossword clue is the 12 letter word PIED-A-TERRE
I've seen this crossword clue in The Guardian
P
I
E
D
-
A
-
T
E
R
R
E
More clues leading to the result PIED-A-TERRE
- See Frenchman's housing in this?
- Pad in which Frenchman entertains partner for the evening
- A Frenchman consumes fruit in a his second home in town
- Girlfriend installed in Frenchman’s love nest, maybe
- In Paris, Peter’s guarding girlfriend’s flat
- Accommodation and clothing denied to French revolutionary over time
- Two food items go astray when returning to accommodation
- Mademoiselle, say, moving into monsieur’s holiday home?
- Frenchman hosts meeting in home from home
- Romantic tryst in Frenchman’s love nest?
Buddy explains!

The straight part
We know that "love nest, maybe" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case love nest, maybe = pied-a-terre.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 PIED-A-TERRE mean?
PIED-A-TERRE noun- A smaller temporary or secondary lodging; a second home.
- A house in the city.