I think Nino was completely justified in his grumpines. Those costumes must be a killer in summer. And of course Jun and his strange desire to jump on mascots definitely wouldn't help.
They make a cute couple though. Jun will help Nino to get along with others and not be so lonely, and stop eating cup noodles (hopefully). And Nino won't judge Jun for giving up a stable job to try doing something that he obviously loves.
Thank you for this fluffy romantic story.