Banshee

A banshee is a fairy woman
Who wails when someone's dying
She comes from the Irish lore
And her cry is terrifying

She may appear as a maiden fair
Or an old hag with red eyes
She may wear a cloak of grey or green
Or a shroud of ghostly white

She haunts the ancient families
Of noble and proud descent
She warns them of their fate
With her mournful lament

She is the woman of the fairy mound
The bean sídhe or the bean sìth
She is the herald of death
The banshee of Irish myth.

A banshee is a type of faerie or undead creature that originates from Irish and Celtic folklore.
They are usually associated with death, as they either predict or cause the demise of someone nearby.

Depending on the source, banshees can have different appearances, but some common features are:

• They are female, often the spirits of elven women who were evil in life.
• They have long, tangled hair and wear ragged clothes that flutter around them.
• They have a pale or blue complexion and red eyes from crying.
• They are either very short or very tall, but always have a humanoid shape.
• They can fly or hover above the ground or water.

Banshees are known for their terrifying scream, which can either warn of an impending death or cause it by driving people insane or draining their life force.
Some banshees are benevolent and only wail to alert the family of the dying person, while others are malevolent and enjoy killing living beings.

Here is a funny joke to go along with my answer: Q: What do you call a banshee who likes to sing in the shower?
A: A shampoo-shee!