"If they meant to kidnap someone who could fight, then they didn't mean to kidnap me. I know how to defend myself, but I said before that this body is weak." He manages to keep his irritation in check - barely. "If they wanted me to participate in a real fight this body would collapse on me before I could be useful."

He's exaggerating of course, but not by a whole lot. Without Agito, or his friends to urge him on and re-energize him, his stamina will be even less than it usually was. And it wasn't that great to begin with.