On Friday nights at 9 p.m. Eastern, two rockabilly monsters appear on a YouTube livestream, broadcasting from their home in Cleveland, Ohio. “I’m Janet Decay, the Mummy,” says Janet Jay, wearing scraps of white cloth, fishnet stockings, and jet-black hair accented with a gold headband. “And I’m Grimm Gorri, the Monkey!” Adds James Harmon, dressed in a rubber gorilla mask with a pompadour, sunglasses, and a denim vest covered in pins and spikes. The wall and shelves behind them are decorated with colorful monster masks and knick-knacks. “And you’re watching,”…