The Nanaya Shiki pose is quite a bit older than the Kamina pose. Also, he's holding a knife, not jabbing his finger at the heavens, which suggests he's about to bring it down in a frenzy of slashes. Also his bearing is a bit more reserved than Kamina's, giving more of an effortless impression. It's its own kind of badass.
He's about to throw that knife at you, and as you attempt to deflect it from stabbing into your heart, leap over to your head, grab your head and twist it apart from your neck.
