Konton tasks Nikosen, a sage-turned-apparition demon, of annihilating the Half-Demon Princesses and attaining their Rainbow Pearls. At the village, Towa and Setsuna accepts the mission of slaying Nikosen from Kohaku while Moroha helps local villagers in destroying the demon for his bounty. Towa and Setsuna come to join her but are attacked by Nikosen who demands the rainbow pearls they possess. Towa attempts to join her twin sister and cousin in battle, but her energy blade does not form, which concerns her and puzzles Setsuna, as she can hear her heartbeat louder than she should...