Added "seiyuu joke" and "Nakahara Mai" because I suspect the fact that Nakahara Mai plays both Tokiha Mai (from Mai-HiME) and Rena (the cleaver girl from Higurashi) is what inspired this. I'm also going to add a translation request.

There's a second seiyuu joke here too. Midori is saying "Ni-pah~", which is something Rika Furude would say. Both are voiced by Yukari Tamura.