What do boys mean when they say you are playing with fire?

If the boy says "woman, you are playing with fire", then playing with fire means that under the temptation and provocation of the girl, the boy can't stop and wants to throw her down and do whatever he wants. So in this context, it is a flirtatious remark. If "you are playing with fire" comes from a girl's mouth, it may not be as simple as flirting. Maybe it's because the boys did something wrong or were told not to change. At this time, you are playing with fire in the girl's mouth, which is a warning to the boy.