I think Erio became incredibly popular because of episode 2. He was a guy who actually got involved very quickly with a loli. Making quicker strides than Yuuno and going farther on the screen. So pretty quickly he became a symbol and when people saw Lutecia well he had to get her.
Have to admit I helped push these things along. With my expectations of episode 10 and a Lutecia encounter. Erio has just had people placing hopes on him. He felt up Caro in episode 2 without consequence. The guy can't be stopped
.