I, Who Came From the Abyss, Will Save Humanity Again Today

The Abyss—represents pure annihilation, they possess incomparably powerful strength, following their instincts to devour all life in the world. However, one day, a traitor appeared among them. "Miss Sylvia, it's time to demonstrate your power." "Eh~ but the dessert, hasn't been finished." She is still a manly man today. — Description from novelcodex.org