"Are you leaving?"
"Yeah."
"Come back?"
"Maybe. If there's still a chance."
"Waiting for you."
"Okay."
She came from another world inexplicably and became a nine-tailed fox demon. She accidentally met King Douga. He admired her ability and wanted her to teach Sesshomaru, but she was in need of a safe shelter.
He gave her a peaceful place to live, and she promised him to teach her wholeheartedly.
She and he got to know each other, and they knew that they were people who didn't talk much, but they still had a good time, and they spent a hundred years like this.
After all, there is no banquet in the world that lasts forever, and the time of separation has come. I don't know when we will meet again, and I don't know if we will have the fate to see you again. At that time, I will say to you: Long time no see, and I hope you can echo: Welcome back.
Concept: The original female protagonist is strong, and "Inuyasha" is a derivative novel with Sesshomaru as the male protagonist.