Vaermina is a Daedric princess whose sphere is the realm of dreams and nightmares, and from whose realm evil omens issue forth. She is known as “Vaernima the Gifter” and “Weaver of the Panoply.”
She is seen as one of the “demonic” Daedra, and some have also claimed her sphere ties somehow to torture. Vaermina’s plane of Oblivion is Quagmire. It is described as a nightmare realm, where every few minutes reality shifts and becomes ever more horrifying.
In the quest Waking Nightmare, the Dragonborn is asked to free the people of Dawnstar from Vaermina’s curse.