[Guido]

SakiSaki is the one who's wishy washy not taking the next step and kiss Naoya, in spite of him setting up the mood flawlessly.

Naoya is virtuous to a fault that Shino will eventually fall for him, or rather she'll learn from SakiSaki's mistake and taking the proactive route to admit to herself that she truly likes Naoya.

I mean the four getting separated by the sea of people, and Shino being left with Naoya when the fireworks display is coming close that sounds to me that all the signs are aligning for Shino to be the (un)fortunate winner of Naoya's kiss even if the result may come or not by accident.