The most common and most likely answer to this crossword clue is the 6 plus 1 plus 5 letter word MENAGE A TROIS
I've seen this crossword clue in The Guardian
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More clues leading to the result MENAGE A TROIS
- Blokes get on with Rosa, becoming involved with it?
- Faulty gasometer in a kind of household
- Unconventional household as people get older, or as it evolves
- Lois stripped to take part in wild East German threesome
- Toulouse-Lautrec’s crowded affair?
- People mature — or it’s a disastrous sort of relationship
- Organise mate with alternative arrangement in this!
- A gnome’s irate at fault in asymmetrical arrangement
- Entanglement with Amos, Gene and Rita?
- Crowded House maybe playing a stage in Rome
Buddy explains!
The straight part
We know that "Unconventional household" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case unconventional household = menage a trois.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.