What does the cryptic crossword clue "A 6 sat around, in fact, in "flagrante" (9)" mean?

The wordplay uses an anagram. anagram of SAT + IN + FACT, = FANTASTIC The answer is FANTASTIC.

A 6 sat around, in fact, in "flagrante" (9)

Guardian Cryptic #23232 | 25 Across | 2004-08-27 flower