Hi, I realized how strange the pairing was, and I apologized for that.
It was an oneshot where the god tree came alive as an human(oid?) being after Kagome did her miko dance routine. This I am very sure of.
More details are a bit unreliable because my memory is very fuzzy. I'm probably very wrong, but I believed that it turned out that the wish made on Shikon no Tama changed the past a bit yet Kagome still retained her memories of the adventure. Goshinboku explained what happened to InuYasha, or something, to Kagome.
Goshinboku (I think the god called himself Shin?) said he and Kagome needed to marry each other because other gods said so? I'm not very sure. I do recall that Kagome have two choices: sent him away and be forced to marry him a year later, or have him to stay and get to know each other.
I do know that it was very likely old, probably over three-five years old and it might be deleted.
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But, I'm still looking for it.
So, um, help? Or tell me if it's deleted? Thank you! ;_; I'm desperate-I know it was a good read.
EDIT: Nevermind!
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I found it!
www.fanfiction.net/s/2798012/1/Divine-Love
It's this one. ^_^