if you are then…

A grindylow is a mythological creature that originated from folktales in the English county of Yorkshire.

Grindylows are a sort of “bogeyman” used as a ploy to keep children from getting in the cold water in the area. They were to grab little children with their long arms and fingers and devour them if they came close to the edge of pools, marshes, or ponds. Peg Powler and Jenny Greenteeth are similar water spirits.

In the Harry Potter universe, grindylows live at the bottom of the Hogwarts lake and coexist, and indeed are domesticated by, its resident merpeople.

A somewhat more unfriendly race called grindylows appears in The Scar by China Miéville.

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A grindylow is a mythological creature that originated from folktales in the English county of Yorkshire.

Grindylows are a sort of “bogeyman” used as a ploy to keep children from getting in the cold water in the area. They were to grab little children with their long arms and fingers and devour them if they came close to the edge of pools, marshes, or ponds. Peg Powler and Jenny Greenteeth are similar water spirits.[1]

In the Harry Potter universe, grindylows live at the bottom of the Hogwarts lake and coexist, and indeed are domesticated by, its resident merpeople.