"Come, Kady." Dr. Rivera beckoned me into his empty classroom. The overhead lights were off; the only light was the yellow glow of the green desk lamp from his desk.
I almost lost my nerve but entered and closed the door behind me. It was only four and Dr. Rivera's art history class didn't start until six. I was overcommitted and failing. I'd tried to drop the class but I was too far into the semester and a failing grade would tank my stellar GPA.
"Closer," said Dr. Rivera. His face was handsome enough. Intelligent dark eyes and a rare but winning smile. He was more than twenty years older than me and probably married. He was also heavy set; his wide, strong body dwarfed my soft and curvy one.
After class last Friday I'd offered my body for extra credit, terrified he would report me but instead he reached his hand under my skirt to feel me through my cotton panties. He told me to arrive two hours early on Monday in a g-string and the shortest skirt I owned. A bra would not be necessary but I should wear heels. Bring my backpack because I wouldn't have time to go home first.
"Pull your skirt up," he told me when I approached his desk.
I blushed darkly and did as I was told. Dr. Rivera gave me a thin smile. "Turn around."
The g-string was invisible between my large, round ass cheeks. I swallowed hard and turned back to face him.
"You're a real slut, Kady," Dr. Rivera told me. "You must be very popular in the dorms."
I stared at the floor feeling overexposed.
"Or maybe you're not interested in college boys at all. Or girls," he added as an afterthought. "Maybe you only want your holes stuffed by someone capable of controlling you, deciding your future. Does that sound right, Kady?"
It was but I didn't want to admit it. Still, I had better say something. "Y-yes, Dr. Rivera." I stammered.
"When we made this arrangement you wanted insurance that I would actually bump up your grade if you performed well," said Dr. Rivera. "I spent all night thinking about that, Kady. You want insurance and I want to keep my reputation. I'll give you your insurance, Kady. Anytime you're ready to quit, you can pack it up. Leave now and you'll keep your grade. It's Monday, and I'll be here marking every day from now until Friday, between four and six. Every day you complete your assignment-keeping me amused until class starts-I'll bump your grade by 20%. A fail to an A, Kady, think about it."
I was thinking about it. I would graduate with honors. Five days of sexual service was all he wanted. I nodded.
"You want your insurance, don't you Kady?" Dr. Rivera smiled and this time it was downright menacing. "Lay back on the desk and spread your legs."
"Here?" I panicked. "What if someone sees? There's a window in the door, it's not locked-"
"Shh," he held up a hand. "I'm not fucking you on the desk. But this is insurance you get so if you want it, get on my desk and open your legs."
Slowly I began to move the stack of essays from where I wanted to sit but I felt a sharp blow on my ass.
"Don't touch the papers, Kady. Just get on the desk."
I did awkwardly, and opened my legs.
"Wider," said Dr. Rivera. He held a sharpie in his hand. "Don't move."
He wrote in sharpie on my hips and inner thighs in scrolling, loopy cursive. I couldn't read it from my vantage point. Immediately above my pussy lips he wrote something I did recognize-his signature-Dr. Alex Rivera.
"Give me your phone," he ordered.
Shaking, I reached into my backpack and pulled it out. I opened my mouth to protest but he cut me off.
"I'm not calling anyone, Kady. I'm not sending anything. Give me the phone."
He took a picture of me with my legs spread, pussy exposed and covered in his writing. He turned the phone to show me what he'd written.
"I promise to grant Kady extra credit of 20% per day she proves to be an obedient slut. - Dr. Alex Rivera"
I couldn't stifle a moan. The picture didn't show my face but I love seeing his writing on me like he owned me. He returned the phone to me and I tucked it away in my bag. He grinned this time and pulled me by my hair back to a standing position. I moaned again, unable to help myself. He opened his left desk drawer and extracted a long black dildo with a wide base.
"I'm going to train you to get this inside you, Kady. It probably won't happen today but I have faith in you to take it all with practice. I have some marking to do today with those essays you were worried about getting all wet. You're going to spend the week under my desk with my cock in your mouth, trying to fit this inside you. Do you understand and consent?"
His hand was still twisted in my hair. I felt moisture pooling between my legs. "Yes, I consent."
"Good. There will be no need for you to talk unless I ask you a question. I will expect you to swallow my cum unless you would prefer to take my class with it all over your face, do you understand?"