Hentai adaptation based on visual novel of the same name. The story is about a mysterious island located at the south of the sea. You can only get there by boat that goes every week. On the island, there was huge luxurious looking hotel built on it. One day, when there was a party at the hotel, suddenly, chaos erupted. Parasitic monsters with tentacles appeared out of nowhere, causing panic among the guests. Some hid, others fought back, and still others tried to flee the scene in a desperate attempt to escape the deadly threat. But as the guests navigate through one dire situation after another, one question remains: is there any hope of survival from those lewd creature?