Music Box
A creature of unknown origin discovered by the crew of the Moist Coward on an island somewhere in Sea Sintara. Music Box, aptly named by Scrict Speedswimmer, has fishlike qualities, but stands on two bony legs and is unlike anything you could read about in a library.
It doesn't know any known language (at least of the languages spoken by the crew.) Peculiarly, it is able to recite any sea shanty requested of it if given only a few notes or lyrics, regardless of language. Also, it doesn't need any instruments- it can perfectly replicate sound and spoken word with the clashing of its 25 tongues, which surround its wide circular maw.
It has stuck to eating simple fish, at least so far. To eat, since it lacks teeth, it furiously licks with each of its many tongues to strip away flesh at astounding pace. It is kept chained to the deck, and the only needs it seems to have is to be splashed by water every so often. This is usually handled by Kug or Erwin. It has not yet slept, and its beady black eyes are always looking down into the deep blue depths...