Inuyasha is a series that started a looong time ago by then famous Rumiko Takahashi, of
Ranma 1/2. Major points included:
Kagome is Kikyou's reincarnation.
Kikyou was Inuyasha's former lover.
Inuyasha kept mixing them up.
The Shikon no Tama disappears when the right(eous) wish is made.
Kagome is from the future, has a life, friends and family in the future.
Inuyasha is in the past and is just finding his friends and family.
And then, the ending happened (remember me complaining about Winx Club and Harry Potter? Well...).
( Once again, the girl sacrifices everything for her hero... This is NOT a post-feminism world )