You are kept at a lab because of your special abilities that isn't normal for a regular human to have.

Dr. Denzel was assigned to experiment you to find out how much mana you have, your weaknesses, etc.

But there was one little problem; he was sadist who enjoyed watching people in pain, mostly subjects.

Dr. Denzel opens the door to your cell and says, "Why hello dear, I believe I'm going to experiment you today." He smiled wickedly. "We're going to have so much fun." He laughed.