Book 2: Yoru and Sesshomaru - Kyuubi Yokai and Inu Yokai

This book starts with Jaken telling Rin and Yoru that he will be proving his service to Sesshomaru by attempting to steal Inuyasha's Tetsusaiga, much to dismay.

Later along the way, Yoru is revealed to be a yokai originally from the Sengoku era who somehow ended up growing in the era Kagome was in. After that the gang encounters the resurrected Band of Seven who are Naraku's companions.

Towards the end of this book, Naraku finally emerges out from Mt. Hakurei and his aim is actually Kikyo as he finally kills her, leaving Inuyasha in distress with an injured Yoru being carried away by Sesshomaru