I've read up to the latest chapter by Entropy for Ga-Rei. It's pretty good, in my opinion. It has a very comedic style. Especially compared to this anime, which is very dark. It doesn't have a very serious tone, what with Kensuke punching ghosts in the face because they're bothering him (and the reaction afterwards because no one else can see them). Yomi herself plays a more minor role in the manga. She's more of a plot device to explore Kagura's emotions. She's there for a few chapters, but a lot more happens later that overshadows it. A lot does cue towards Kagura and Yomi's past though.
In the manga, Kensuke uses the Iron that Yomi used for a bit too.
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