That Demon, Possessive [Yandere!Sebastian x Reader AU]

You are currently in a basement, encased by a cage. The raven has you trapped, and you fell right into his trap. Accidently, of course. Allow me to explain how you got into this situation.
You're a high school student with all honors classes. You've always been that typical straight A student with a bunch of hard classes. There was always one class that was extra challenging, and that was History. The teacher was... Different than all the others you have. This one, he spoke words even you could barely grasp to understand. He always had this certain aura that you were so curious of. This is where he had lured you in; Grasping your attention, you wanting to know more about the mysterious teacher. You weren't exactly 'attracted' to him like everyone else, but he was attracted to you. Now this is where you messed up again. He tends to be 'possessive'. This teacher was known as Mr. Michaelis, otherwise known as Sebastian Michaelis, the male that use to be Ciel Phantomhive's butler. Ciel had disappeared randomly one day, and that was the day Mr. Michaelis started his job at your school. What ever happened to the Young Lord now, hm?