Author's note: Welcome to my first attempt at a Cthulhu fic. Yes, it involves Rosario Vampire, but after seeing the first season, I kept thinking "You know what would be really interesting? Monsters from the Cthulhu Mythos. Come on, Inner Moka vs Star Spawn!" Otherwise, I hope you enjoy.

Disclaimer: The following is a non-profit fan-based piece of fiction. Call of Cthulhu and Rosario Vampire were created by (as far as I know) H. P. Lovecraft and Akihisa Ikeda respectively.

Chapter 1: Invitation

Some humans believe they are alone in the universe. Others… know they are not. One such person was running down a street: Rin, a late-teenaged girl with shoulder-length white hair tied into a ponytail. She had received an invitation to go to a school filled with monsters of folklore: Yokai Academy. The accompanying letter specified how she was a witch, and therefore deserved the chance to study away from a repressive human environment.

Rin kept running, her arms happily flailing at her sides, taking corner after corner until she came to a house. The house wasn't much to speak of: a small 2-floor house, and were it not the place the girl chose as her destination, it would have remained indistinguishable from the rest with its white walls, brown roof, glass windows and tan door.

As Rin drew closer to the door, she extracted a wand and aimed it at the handle. One flick of her wrist later, and the handle turned by itself, the door creaking open soon afterwards. The pace was clearly too slow for the girl, so as soon as the door was slightly open, she grabbed the handle and threw aside the barrier in her path.

"Misa-chan!" she yelled. "Miiisa-chaaan!"

"Wait!" a boy shouted with panic, running into the room. This boy, although wearing plain clothes, had white hair similar to Rin, except his hair reached only to his neckline and was much smoother than hers. In addition, one could make out that his hair 'fanned out' so as to have a larger width from his head such that, in a few years time, one could see him having shoulder-wide hair growth.

"Aw, Sora-kun, where's Misa-chan?"

"Misaki-Onee-chan is asleep, Rin-Onee-chan."

"Call me Rin-nee-san. Why is Misa-chan asleep? I remember her promising to stay up to gaze upon my newly acquired treasure."

"I don't know. She spoke of 'the urge' before she went to bed."

"Well, Sora-kun, while Misa-chan is busy tossing and turning, how about a little game?"

"What?! Why? I don't want to have my own shirt trying to blind me!"

"Don't be such a spoilsport. I promise this game won't involve any magic."

"That's what you always say, yet the bushes continue rustling to give my location away in hide-and-seek!"

"Quiet down!" a third voice boomed. In the passageway stood a woman with shoulder-length, free-flowing white hair stood, dressed in cyan pajamas, her sea-blue eyes struggling to stay open. "Sora, I thought I made it clear that I was not to be awoken."

"I'm sorry, Misaki-Onee-chan!"

"Good afternoon Misa-chan," Rin spoke. "I got the invitation from Yokai Academy!"

"Does that include a second, blank invitation?" the Misaki woman asked.

"Yes, why? Are we admitting Sora-kun early?"

"No, the plan has changed. Sora will remain here. Master has spoken to me, and-"

"Our 'Master' doesn't really speak, does he?"

"Do not insult our Master. I have seen someone new, someone to whom the second Yokai invitation must go, and soon. If he receives the invitation and goes, he will be a suitable sacrifice for our lord and Master to rise up from the waves."

"Who is this kid?"

"Aono Tsukune."