Episode 9

S7, E9: Sesshomaru asks his mother how he can expand Tenseiga's Meidothe Path to the Underworld. In response, his mother uses the Meido stone that Sesshomaru's father gave her. However, Kohaku and Rin are swallowed by a giant dog and are taken away to the Path to the Underworld. Sesshomaru chases after them and steps foot into the Meido, from which there is no coming out alive.