I completed the Dark Brotherhood quest for http://elderscrolls.wikia.com/wiki/Muiri about forty game hours ago, so I'm not sure how feasible this is, but I think something amazing just happened.

Wandering around in Markath at night, I step out of a house by a river, and crap myself as a falling shape hits the stone path in front of me. After brief hyperventilation () I wander over to see what's happened. It's Muiri! She fell a long way. Looking up, the only detail I can see is a jutting ledge, with no balcony. The side of the building is sheer, and I can't find my way to where it happened. Being the conscientious soul that I am, I dispose of Muiri's items, and drag her body into the river, to be washed away to the great seas of Tamriel.

Anyone who's done the quest for Muiri knows that it's morally... dubious. What I'm wondering is, is the AI/scripting in the game so advanced that my actions have caused Muiri to kill herself from grief at what shes' commanded? If so, I'm seriously impressed. Though I'm also aware of the possibility of a glitch that spawned Muiri forty, fifty feet above a stone slab, which is never combined well with physics.

LOL, that's gotta be a bug... but a very timely one, in your case.
-Loth

I don't find Muiri's quest morally dubious. Excessive? Perhaps. She certainly seems to be a touch on the crazy side/over-emotional side, but that's part of why I love her. Not to mention, she's one of the few marryable NPC's that actually goes beyonf thanking you. She says "I'll never forget you". That was delightful, and one of the reasons my character married her.

Visit the house of her victim's family. There is more to follow for that quest.

As for her apparent suicide, She never did so in my game. So I think it is just one of those random NPC pathing deaths.

I can't speak for the NPC in question, but I see and find dead guards that are/have walked off of paths with fair frequency. Bandits do it at a couple of the exteriors of Dwemer ruins, as do Falmer in interiors.

Curves and corners on a high path seems to present a pretty high percentage for NPC death, especially if there are stairs or ledges involved and they do that teleport thing to get "unstuck". Wheeeeeeeeeeeeeeeeeeeeeewwwwhhh-splat.

I decided: One black scarement, one assassination. Not to mention I have to go through you're entire boyfriend's gang to get to him. I'm not taking an innocent life so that you feel better. I may be be an assassin, but what you're asking me to do is just plain cruel. No-way, no-how.