Ayame-senpai, the Oni, told the girls of an entrance to the underworld on Mount Osore in Aomori. She herself had never been to the land of the dead, but she assured that if the one they were looking for was what they said, they would find her there.
Ina covered them in a protective spell. Normally, living beings couldn't enter. Banshees and demons ignored them thanks to the spell, but not even Ina knew how to cross the Styx.
While Watson investigated, Kiara disappeared.
They found her ahead, talking happily with a hooded being.
"Girls! This is Steve. Our ride."