This list of mythical creatures that begin with this letter and I am constantly gathering information from each continent, and is continually being updated.
Loogaroo (French America)
The Loogaroo is a monster found in Caribbean mythology. Oddly enough, its name is pronounced the same as "loup-garou", French for "werewolf", despite having nothing in common with werecreatures. According to the myth, the Loogaroo is an old woman who is said to be in league with The Devil. She will have magical abilities only if she gives the Devil blood every night.
She tries to give him blood of other creatures, or else he will take her own blood, causing her to die. The Loogaroo can leave its own skin and turn into a flame or blue ball of bright light that haunts the night searching for blood to meet the terms of her deal. After she has collected enough blood she can return to her skin and retake human form.