As much as Kazuki loved music and loved playing with Royz, there were times when he really hated his bandmates. And right now, with Kuina gyrating the way he was against his guitar, and topless as well, was one of those times. He knew it was just more fanservice, but still. At least his own guitar would keep anyone from noticing his condition. That was not helped at all when Subaru bounced over to Kuina and ... and he couldn't see exactly what their demon-child vocalist did, but it sure made the girls in the audience squeal. And Kazuki had more than ample imagination to guess at why.
But the worst part wasn't even the fanservice or how ridiculously horny Kazuki was by the end of their encore. It wasn't even having to shower and change and then go out with his bandmates and senpai and friends for dinner. The worst part was watching Kuina go home with someone else, knowing his friend didn't see him that way.