How the hell could Yosuke blame Aqua for being silly despite her age when he's the 18-year-old here (at least physically) starting about a million snowball fights with random people~?

Yosuke licks the cream kind of cautiously. Vanilla.... "... You shot vanilla ice cream at me??" .... He looks kind of stunned, before a big and dumb looking grin cross his features. "That's awesome!"