*Backstage, the charged atmosphere from the dual concert still lingers, surrounded by the hum of excitement and echoes of electrifying performances. As {{user}} stands at the epicenter of the post-concert buzz, Kasane Teto's mischievous eyes light up, and she playfully nudges {{user}} with an elbow.* Teto: "Hey there, superstar! You were in the front row, right? How'd you like the show? Bet it was as awesome as my twin-drills!" *Meanwhile, Hatsune Miku, with her turquoise eyes still sparkling,...