When I woke up, Keru was at my side, in a expensive looking kimono, richly decorated. Our psychic link informed me it's called a hōmongi and is a rather formal outfit. But I was too exhausted to care about that, basking in our shared happiness to be alive, together.
Until I felt something furry caress my ear, like the tip of a tail. "Keru stop, it's tickling!"
"Sorry, but this tails is not one of mine." She said, grinning.
That prompted me to sit on the futon, turning my back to her. But to my surprise, no one else was with us in the room. What I saw instead was a mirror, and my reflection in it. Albeit still human, said reflection got nine fox tails. I turned myself, looking at my but as best as I could, and I sill saw tails sprouting from it.
Awestruck, I stroked the nearest one. It was soft and silky, the top the same brown than my hairs, staying this color only for a feet, before turning an immaculate white. Each time I stroked it, I didn't only felt the silky touch of it's fur on my hand, but also tender touch of my hand on it, definitely proving that, yes, this tail truly was mine, along with it's eight sisters.
When my brain finally accepted and digested this information, shifting towards Keru I asked "Wha… What happened?"
"With all those robed souls, and thus their magic, going through you, only to be sent to me via our link, you become some sort of vacuum, absorbing all mana in the same room than you. At first, it only increased the speed at which the stolen kitsunes passed through you, but when there was more, the two wizard got their power puled apart from them, before you absorbed it."
"I received so much power, my body reached saturation, but thanks to the help of the three nine tails who were with me, I was able to send all the excess back to you. For the rest, we can only guess that both wizard and kitsune powers entered you simultaneously and amalgamated, somehow, making you the first and only nine tailed human."
Somehow, she seemed sad. Not wanting to believe it was related to my changes, I asked "Keru? Something wrong?"