[Nag...ging.... you know, you could say that he nagged, or you could say that he infiltrated a high security prison in order to bring out valuable information that would be of worth to Sousei--

... hm well.]

Something similar, I suppose. He is very hard-headed.

[And Sousei is really, really fond of him. But nonetheless...after a moment's pause, he continues:]

Yes. But even so, if he disappears again, there will be nothing I could do. Much like the case with you or me as well.