S1·E5 Aristocratic Assassin, Sesshomaru

Kagome learns that Inuyasha is a half demon, born of a human mother and a dog demon. Inuyasha's half brother Sesshomaru appears, looking for the tomb of their father. In order to manipulate Inuyasha, he brings Inuyasha's dead human mother with him. But the woman turns out to be a demon known as a muonna.