Ammut

"A demoness from Ancient Egypt, Ammut lived in the Hall of Ma'at, where the dead awaited judgement. She had the head of a crocodile, the body of a lion, and the back end of a hippopotamus; the three most dangerous animals in Egypt. When the dead's soul was weighed against a feather Ammut would devour those with heavier, more sinful hearts."

The beginning creature of Kory Bing's 'Bestiary Alphabet', Ammut is a legendary figure in Egypt. As stated, Ammut ate the sinful hearts, letting the good ones free.