I may be reaching, but is it possibly 'Death's New Mistress' by Quiet Whisper?
Using the jewel to restore the lives of those lost in the battle against Naraku, Kagome's life is taken in exchange and she is also given a task. But collecting souls isn't the only thing she is capable of, or so she soon comes to discover when she's called upon to aid one she knows in battle. By the way, did you know you could evoke Death to fight at your side if the situation was dire enough? Won 1st place Best Darkfic/Horror 1st Quarter 2010. Won 1st place Best Kagome Portrayal 2nd Quarter 2010. Thanks!!!
Link:
www.dokuga.com/fanfiction/story/3143/1
Rated MA so no YIM's please