Probably won't get to the event until tomorrow. But tossing my ideas here so I don't forget them.
Senri is going to mostly ignore the fireflies, which means he's probably going to get blighted when they land on him.
Cardia will be a mess because forget blight, any firefly that lands on her face will just dissolve and she'll feel awful. And be worried that someone noticed.
So that'll be fun.
Hiyoko I'm not sure. She'll certainly be up for fighting some ayakashi.