Well, if it helps, most of the stories I have going right now are lighter! (Other than the one I just started writing). "Blooming Narcissus" is an exceptionally long story, at least in my head, so it will be a while before I start writing it anyway.

And I want Harry to kill Narcissa because I'm interested in having him commit a genuine crime/make a genuine mistake, and then seeing what he does about it.