Grum of Thrones

The encounter

Humans and elves can interbreed and produce half-human, half-elfin children, who often have the appearance of humans but possess extraordinary intuitive and magical powers. Humans can apparently become elves after death, and there was considerable overlap between the worship of human ancestors and the worship of the elves. The elves are luminous beings, “more beautiful than the sun,” whose exalted status is demonstrated by their constantly being linked with the Aesir and Vanir gods in Old Norse and Old English poetry.

THE ERL-KING.

Who rides there so late through the night dark and drear?
The father it is, with his infant so dear;
He holdeth the boy tightly clasped in his arm,
He holdeth him safely, he keepeth him warm.

"My son, wherefore seek'st thou thy face thus to hide?"
"Look, father, the Erl-King is close by our side!
Dost see not the Erl-King, with crown and with train?"
"My son, 'tis the mist rising over the plain."

"Oh, come, thou dear infant! oh, come thou with me!
Full many a game I will play there with thee;
On my strand, lovely flowers their blossoms unfold,
My mother shall grace thee with garments of gold."

"My father, my father, and dost thou not hear
The words that the Erl-King now breathes in mine ear?"
"Be calm, dearest child, 'tis thy fancy deceives;
'Tis the sad wind that sighs through the withering leaves."

"Wilt go, then, dear infant, wilt go with me there?
My daughters shall tend thee with sisterly care;

My daughters by night their glad festival keep,
They'll dance thee, and rock thee, and sing thee to sleep."

"My father, my father, and dost thou not see,
How the Erl-King his daughters has brought here for me?"
"My darling, my darling, I see it aright,
'Tis the aged gray willows deceiving thy sight."

"I love thee, I'm charmed by thy beauty, dear boy!
And if thou'rt unwilling, then force I'll employ."
"My father, my father, he seizes me fast,
Full sorely the Erl-King has hurt me at last."

The father now gallops, with terror half wild,
He grasps in his arms the poor shuddering child:
He reaches his courtyard with toil and with dread,—
The child in his arms finds he motionless, dead.

I better read up more about elves and their king, they sound dangerous.