having a fling = having a love affair / romance

Thank you Seth!　I'll remember: With+Person :)

Great question! Usually we say a fling is with a person or a hobby. A fling is always temporarary. ´´I had a fling with him last year´´. (it means the two people dated briefly) ´´I´m having a fling with learning French´´ (this is not as common, but I have heard similar expressions)