I'd taken the sex ed course in school already and had gone through a few of these things from when I hit puberty, but this...*this*...this was nothing like any I ever had before! It was hard enough just for me to sit up in my bed because even the lightest touch of the clothes I had worn to bed - sweatpants and nighty - against my body was sending waves of pleasure all over. I could feel the heat coming from "down there", seemingly pooling in my breasts as they began to warm up and expand before my eyes, pushing out against my nighty and making it start to feel a little tight. I kept my legs crossed like I was trying to hold it in, even as I placed my hands to cup my breasts, feeling them expand in there and making it really hard on myself not to stick one of them down my pants. But oh, it'd feel sooo good to do it...
It was almost a blessing really when the pain in my temple took my mind off of the rest of my body. I put my hands up there out of instinct and was surprised to feel something solid and smooth there. I looked over at the vanity mirror across the room from my bed and gasped when I saw what was there: it looked like bone spurts coming out of my forehead, growing slowly but surely larger. A sharp pain in my lower back made me cry out a bit, in pain from whatever it was and (if I'm being totally honest) in pleasure from all that rubbing of my clothes on my hyper-sensitive parts. Another sharp pain in my lower back made me arch up, the feeling from the rubbing of my skin on clothing quickly covering the pain, followed by the feeling of...*something* growing against the seat of my pants. I managed to gingerly get up on my knees and turn my back towards the mirror to see something long and relatively skinny start to grow down a pant leg.
When I noticed the triangle-shaped end of it as it neared the opening at the bottom, I realized what it was and the curse was doing to me today: that was a demon's tail, and it was turning me into a succubus!