I think you are searching for this fic:
www.fanfiction.net/s/3927981/1/Simple-Kind-Of-Life
Simple Kind Of Life
By: sleepymuse
Changed from dog fighter Kagome leaves the feudal era for a normal life, but her guilt makes her return. The well sends her to another world where she finds Sesshomaru and she brings him back with her. A slip makes her claim them both. SXKS
Rated: Fiction M - English - Romance - Sesshomaru, Kagome H. - Chapters: 26 - Words: 40,240 - Reviews: 230 - Favs: 208 - Follows: 87 - Updated: Feb 22, 2008 - Published: Dec 4, 2007 - Status: Complete - id: 3927981
Rated M, so no YIMS please.