Sissie

Sissie (シッシー) is a lake monster that was shown in the spin-off manga series The Ways of the Monster Nation. It is known to reside in Lake Sis of the Great Jura Forest.

Appearance
Sissie is shown to have the appearance of a large shark similar to a regular megalodon, with 2 semi-spiraling horns on the side of its head and features 3 rows of teeth.

Personality
Sissie tends to swim away from those with a powerful aura.

Trivia

 * Sissie, an analogy with Issie, said to be a Japanese lake monster in Lake Ikeda, on Kyushu Island.