This is what they call a core memory: Watching the night sky light up with fireworks while dancing in the rain, as your favorite K-pop boy band plays their greatest hits. Much like Taylor Swift's Eras Tour, K-pop touring is a behemoth of an economic machine, rolling across continents and reaping in billions. I've been a willing participant, watching the boy band Seventeen perform five nights in three Asian cities. Every stop was enjoyable, but one night of the tour was by far the most memorable.