Okay I give up looking by myself and hopefully someone else will know what I'm talking about. I believe this is a multichaptered story but I'm not a 100% on that. All I really remember concretely is the end chapter. Which goes something like this:
Kagome is trapped in the future. She's pregnant and Sesshomaru doesn't know. Roughly 5 years or so she goes out to dinner with Hojo because he helped her get her yoga business started. She's wearing her mother's wedding ring because she got tired of guys hitting on her. She told Hojo that Sesshomaru was in the military and that was why he was never around. Hojo still loves her obviously.
Skips to Sesshomaru as he arrives in Japan via airplane. He feels the mating bond goes by the shrine meets Kagome's mother. She tells him that Kagome's with Hojo and he leaves to go after her. Mama calls Kagome to warn her and Sesshomaru walks in. They kiss and end up going back to his house. He gets her pregnant again because he doesn't know about their son. She takes him back home to meet their son and that is all I remember.
So thanks in advanced!
(Specially if you actually read all that!)