We are familiar with leprechauns, although the American version from the Lucky Charms package isn't quite the original. There are plenty of other creatures from Irish folklore you can learn about in this list. Have you ever heard of the Bean Nighe?
The Bean Nighe is the spirit of a woman who died in childbirth, condemed to wash blood the shrouds of the soon-to-be-dead for until the time at which they would have died of old age. The spirit has one nostril, one long fang, sagging breasts, and webbed feet. If you're brave enough to steal a suck off her breast, you can claim status as her foster child, and she will grant you a wish.