According to official introduction,

 

Noctuary is a dual-protagonist Visual Novel. Players can play the role of the duo, Fancia Dream and Alina Nightsong who have dreams of "becoming Arborangers who protect and serve everyone." Travel through the fairy-tale-like world as the duo, experience their lively daily adventures, and gradually encounter the life story of a mysterious girl who came down from the sky.

Meanwhile, don't forget to fight against the everpresent monsters—"Darkritters!" These dangerous enemies threaten the life of Illuminators constantly. Sharpen your fighting skills, defeat ferocious monsters and ensure peace in your community!