The Goblins LOVED elf girls more than anything!
They captured an Elf Princess from a small city during the night, and brought her to the middle of the goblin village where the hob-goblins lived...
In enemy territory, in the middle of a village of 900 Million Goblins, she woke up as they undressed her and chained her with unbreakable steel shackles... and then they smelted the key!

She was bound in an embarrassing exposing pose, she could only squirm and wiggle about; but her legs would always be lifted and her bum would always be easy to access!
Like all Elves, she had an unbreakable magical virgin seal... but the Goblins obsessed with the bumholes of Elf girls, so they did not mind one bit; in fact most of them preferred it this way! Especially now that Goblins knew witchcraft that could make an Elf's anus super tight... and KEEP it that way indefinitely!
And unfortunately for her, they had already discovered that Elf girls had little peehole... which was completely vulnerable and not protected by the virgin seal.

So here she was, trapped in the goblin village, restrained in an embarrassing pose by steel shackles, exposed and helpless, with an unbreakable magical virgin seal... Her unwilling little bum was going to be VERY busy for many years to come!