“I’ve done regular karaoke, never with this kind of crowd,” Cooper, 35, says later, hanging out by the bar. “It’s like a performance; you have to engage the crowd and be entertaining.” ...

Usually, when you sing karaoke in Japan, you either sing it in a bar, or at a room at a karaoke parlor, or maybe somebody's house. But those ways involve other people.

Coin karaoke booths are compact, with most designed to fit no more than two people. There's usually one remote control, two microphones, the display screen and a slot to insert money.