Black Seppuku Rabbit

Seppuku Kuro Usagi is Akane's messenger sent by the Moderators. Like all the Entrails, it has its ïntestines sticking out, and blood on its mouth.

From what Akane exclaims when she is in her Kämpfer mode, it was mentioned that Seppuku has a voice similar to Tamura Yukari.

Obviously, Yukari Tamura is its seiyuu.