Raion Hiaburi

The oldest Messenger, its existence said to pre-date the Zōmotsu Animal toyline. The novel version of it does not have its guts hanging out of its body like the Zōmotsu Animals after it, but the anime version does. It has the same shape as a character which Kaede imagined before, with a voice similar to that of a voice actor who performs voice-overs for foreign movie stars. Kaede got it by mere chance though it is very scarce. In episode 11 of the anime, it reveals the reason behind the Kämpfer battles.

From Wikipedia.