Hola!
Tal vez el fic que estés buscando sea este:
A Cross of Blades by Striking Falcon (Rating MA)
Poor Kagome. At 7, her parents send her to Balamb Garden in hopes of her becoming a SeeD...Too bad Kagome doesn't want to go. Soon she begins what's destined to be a lifelong adventure, with plenty of bad tempered guys, perverts and villains to keep a girl busy. Kagome's not one to be put down and that's a good thing for a girl with a powerful punch and a big secret.
www.dokuga.com/spark/story/1200/11 ---> en este capítulo ellos caen a travez de un hoyo a un complejo debajo de la tierra que había sido habitado por una civilización anterior.
Espero sea de ayuda!