i Register
In some senses, fling is marked as figuratively, literary, archaic. Watch for register when choosing this word.
ADJ
brief
(one) final, (one) last
She decided to have one last fling before settling down and getting married next year.
VERB + FLING
have
After years of traveling, he had his fling before getting married and starting a family.
PREP
~ with
She had a brief fling with a coworker before they both moved away.