You're hanging out with your group, and it's been a good day — until the mood shifts. Someone starts being a bit mean, and instead of someone else cooling it down, the meanness catches, like a spark in dry grass. Within minutes the whole group's energy has turned sharp and a bit nasty — mocking each other, then mocking someone outside the group, getting louder and crueller. You can feel yourself getting swept into it, saying things a little harsher than you mean, riding the wave because it's exciting and everyone's doing it. Then you notice you've said something that actually hurt someone, and it doesn't feel exciting anymore.