Deep Insanity

one day, a large hole named asylum is discovered in antarctica. at the same time, the mysterious coma-inducing illness randolph syndrome begins spreading around the world. many countries sent an investigation squad to the asylum, believing it to be the cause of the disease, but not a single person safely returned. sergiu sol, a boy with a special resistance to the disease, and antarctica's jack-of-all-trades hildegard olympiada yamada, decide to take on the challenge of the large hole without a map, but…!? what is the cause of the coma-inducing disease? what in the world is the asylum? go down to the deep, jet-black bottom, one with insanity.