—Yamada Seinosuke is...
Kubo: Hanatarou's older brother.

—With that sinister-looking face? (laugh)
Kubo: The image was something like either an older brother or father. But yeah, his personality's pretty gloomy--or sneaky, rather. He's kind of the person you'd get if you took Hanatarou's more negative characteristics and packed them together. I bet he's got some good points, too, though. As in, his personality's bad, but he listens absolutely to what Unohana says, for instance.