Board Thread:Lore Discussion/@comment-16375955-20130824112156/@comment-3573184-20130827230741

PsijicThief wrote: 15 orignally created by Sithis Sithis didn't create the Daedra, the Daedra are just et'ada that formed from the interplay of Anu and Padhome that are more Padomic like, choosing to be chaos based.

Also, Mehrunes Dagon isn't a true daedra, but rather a creation of the magna-ge, the spirits who fled creation with Magnus, and Meridia is believed to be a manga-ge who was cast out for consorting with other spirits.

Making both of them not true Daedra, along with Malacath.