[ If Yu is surprised, Yosuke is even more. He blinks. ]

...Hundreds of years??

[ Well--wait, it...it makes sense, right? They've been writing since forever. The Watatsumi Mikoto learned it long ago and passed it down to their offspring--the same language that humans were taught, right? Or something like that. He vaguely remembers from his own studies, but Yosuke doesn't really commit much to memory if it doesn't interest him, and lessons never really did. ]

So...they gave you other characters to write with, or...you guys...made up your own alphabets?

[ He raises his brows. And then whistles. ]

That's...actually really impressive.