Forever with Lord Sesshomaru
Rin has her doubts about whether or not she will be with Sesshomaru forever, after Jaken tells her that he and Sesshomaru will probably live longer than her, because she's mortal and they're demons.
Aired 09/08/2004EP 162 - Forever with Lord Sesshomaru

2000
InuYasha
Kagome Higurashi, an average ninth grader, gets pulled into an ancient well by a demon, bringing her 500 years in the past to the feudal era. There, she meets Inuyasha, a half-demon who seeks the Shikon Jewel to make himself a full-fledged demon. With Inuyasha and new friends, Kagome's search for the Jewel of Four Souls begins...
(Source: VIZ Media)