The hat on top of the matching helmet amuses me, especially paired with her unchanging expression.

i thought the hat was part of the helmet...

Better question would be why is Koishi wearing a helmet at all? Protection from the fever Cirno has?

\Atai/ said:
i thought the hat was part of the helmet...

I suppose that's possible too.

xahldera said:
Better question would be why is Koishi wearing a helmet at all? Protection from the fever Cirno has?

She's being Koishi. There really isn't a better explanation.

She does have a door-greeting mask, maybe she has a doorbell-ringing helmet.

6163 said:
She does have a door-greeting mask, maybe she has a doorbell-ringing helmet.

That makes way too much sense.

She brought Suika. D'awww...