User blog comment:Halo1081/Chapter 128 and forward/@comment-4911196-20150302030909/@comment-5707992-20150302035116

Actually Nagisa is a great hitman in general as he's one of the few students who have driven Korosensei into a corner, but you're forgetting that Kayano is still technically human. She just implanted the tentacles in herself. Also, by we still don't know his full potential in terms of bloodlust because some of that was Kayano's.