Running from his past while ignoring his future, Shadowmere arrives in Equestria through a strange portal. How will the last of the Dark Brotherhood forget the ghosts of his past while trying to live in a world where his services are no longer required? And what happens when a threat ignored for the last 200 years rears it's ugly red head in Equestria?

Expect Sheogorath to appear later, along with large amounts of Skooma and cheese.
Credit to BlackWolf1112 for the image.