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From a distance squishers appear human, but according to legend their heads are larger than those of men and they have scales instead of hair. They have webbing between their fingers and toes, while their mouths have rows of green, needle-like teeth. A squisher's belly is white like that of a fish. Their name comes from the squish-squish sound made when they move on their webbed feet.
The First Men are said to have killed all of the squishers, with Ser Clarence Crabb fighting the squisher king. Some residents of Crackclaw claim squishers still come by night to steal bad children, however, saving girls to breed with and boys to eat.
Some or all members of House Borrell have webbed hands and toes similar to the feet of ducks, which they call the mark. It is unknown if this is a genetic disorder or if they have a connection with squishers. It is also unknown if squishers are related to the Deep Ones written about by Maester Theron.
A Feast for Crows
Dick: They'd eat you, boy. They'd eat you raw.
Podrick: If they try, I'll kill them.Dick: You try that. You just try. Squishers don't die easy.