“Ninpo –“
“Harlequin Butterfly – my movements ignore the laws of gravity,” he explained triumphantly, as if to make up for his earlier discomfiture. “I can carry anything, no matter how heavy, and even a branch as skinny as that serves as a foothold for me. You can hit me as hard as you want, but you’ll only send me flying.”
He was simply too light – to be knocked down.
That explained things.
With ninpo that can obviate the laws of gravity, even crossing the sea with two grown men riding on your shoulders would be a simple feat.
“Are you saying that my hand never actually hit you, that the draft my hand made sent your body flying through the air?”
“Yeah. You could say that I’m invincible to all conventional strikes – because I’m physically impervious to them.”

Katanagatari Omnibus 2, Page 56