Finwithit is a sea-green leviathan about 30 feet in length. His appearance suggests a Cachalot Whale, but he is more amphibious; he does not hesitate to enter shallow waters or even to come up onto the land. His level of intelligence remains something of a mystery, but his facial features are quite capable of expressing his mood, even as they also display some of his sharp teeth.
When in the presence of Aquarianne, Finwithit is happy, friendly, gentle and charming...so long as his mermaid charge is in no danger. When Aquarianne sounds her conch-shell trumpet, the leviathan will do everything in his power to come to her side, and when he perceives that she is in danger he will unleash the full extent of his stone-crushing fury.