Don’t know the name of it or the author. Kagome and Sesshomaru are married. Kagome is training to help run the business, Sesshomaru thinks she is cheating so he cheats. She finds out when she come home to tell him she is pregnant. She leaves and later tries to contact him. She haS twins, a boy and a girl. One is full blood the other hanyou. The hanyou has hanyou desease. The woman that Sesshomaru is with is Kagura, they had a little girl together. Idk much after that

I think this is the one you are looking for
url: www.dokuga.com/spark/story/6896/1
title: Deception
Author: JosieKnox
I would put it at MA as I know there ARE scenes in there.
the only difference, is in the women, Sessh is with Tsubaki, although, there could be one similar with Kagura