Utea Charm (Karen) and Utea Grace (Mitsuki) had formed a pact with a mysterious creature named Clio and spent their days battling "lewd beasts" as magical warriors. Although Charm attempts to purify Grace—who has succumbed to the dark side—the two find themselves drawn to one another, eventually drowning in a whirlpool of pleasure. Then, when Grace ejaculates inside Charm, she awakens a new power...