[b]Shio[/b]

Initially Shio didn't understand what kind of preparation Kasumi was referring to. Once Kasumi explained 'if the battle is interesting' she was able to grasp that it was a challenge.

Shio took note of the formed water before replying, "I will battle you."

There wasn't much of an opportunity for Shio to refuse. Kasumi's stature as a Touhou would make it a possible offense to refuse, even if Shio didn't want to. On the matter she was mostly ambivalent, not really caring either way if she got into combat. There were some practical advantages to doing so - mostly that it was a chance for her to solidify the bond between her Kujaku and herself. As well, it provided Shio some of her physical exercise for the day.

There was direction needed as to where to fight. Kasumi likely already picked up that this would be one of the matters that Shio would defer to her on, thus i was on Kasumi to pick the location of combat. There were many options, but likely not within the Red Nakumo's outdoor patio - one of the many 'town squares' would likely be used - a historical convention for most trainers.