Seppuku Kuro Usagi
is a Messenger for Akane in the form of a stabbed black rabbit which has bloodshot eyes. It speaks with a sarcastic tone and has a foul mouth although it is on good terms with Harakiri Tora. Its voice was described as sounding like that of Yukari Tamura, and so she voices it in the anime. In a scene where Natsuru was asked to turn on the TV in the hotel, it stated a preference for watching pay-channel pornography.