Music-lovers attending Japan’s largest music festival, Summer Sonic, have become accustomed to catching sets by the world’s biggest musicians, from headliners Jay-Z and Beyoncé to Coldplay and My Chemical Romance. This year though, a “special guest” closed the show in Tokyo. Girls’ Generation is the first Korean act to close the Japanese festival — and follows in the footsteps of a previous late-night special guest, Lady Gaga. “We feel like rock stars!” said Tiffany of Girls’ Generation, moments before taking the stage. “It’s completely exciting to attend a rock festival when we are not rock, so we are hoping we can give it a different twist for this year’s show.”