In Japanese folklore a shachihoko is a chimera with the head of a tiger and the body of a carp. This fierce sea monster is able to swallow a huge amount of water to store in its stomach, and is also believed to be able to summon clouds and control the rain.

Because of this, temples and castles in Japan often have pairs of statues on their roof in the shape of shachihoko, with their fins facing the heavens. They are believed to protect buildings from fire as they can either spit out the water they swallowed, or cause it to rain, in order to douse the fire.

You can find more information about shachihoko here.