I'd have to agree with Rena as well, she has the eeriest, most unhinged personality once she freaks out, but she behaves as though it were perfectly normal.

If I we're to choose a character based on their "crazy laugh" it would have to me Takano though, the has the shrillest, highest, most ear-piercing cackle out of all of them, despite only ever hearing it in one episode O.o

i'm sorry, what?

i was implying that there is a more sadistic anim higurashi, but you failed to understand that... and you're anon

I would probably agree with you, as she has the biggest personality change out of everyone.