UC: Fates by Amaranth (The Erotic Mind-Control Story Archive) A story about students at a magic school and those using them for their own goals.
Dark Incarnate Book 1 and 2 by Mr Black, Science-Fiction Erotic Horror, Tentacles, Native American Lor, magic, Dark vs Light.
The Wraith Spider by Jashin (Naked Blades website)
The Magicians (Syfy TV Show and a book trilogy)
Deviantart:
Beware of mimics by Heartzmd (a very similar to your pic Commission)
Necrovert (The Delve is a great D&D, with more than some nudity, story)