Sound of Drop: Fall into Poison

In the heart of Tokyo lies the picturesque little aquarium Manten Aquarium. Numerous urban legends entwine around the aquarium. On the night of the full moon, the water turns bloody and man-faced fish lurk in it. High school students Mayu and Himeno came to the Manten Aquarium to investigate these legends. It was fun at first, but then.... they catch a glimpse of Mayu's missing little sister, Mari. The wheels of fate begin to turn as they track Mari's shadow.