The Biology of Music - I fucked my trans substitute teacher

Until she looked at me, and I realised I might be in a spot of bother.
"You're looking very relaxed there. Do you want to come up to the board and show us the different parts of this plant that are involved in reproduction", she challenges me.
I am desperately trying not to cum because that will be very obvious, but fucking hell she is talking to me and looking at me and my cock is ready to blow. I respond, "Sorry miss. I don't know anything about plants".
"Are you not paying attention? What are you doing down there?"
She makes her way down to my desk. Her legs are so long and beautiful. She is wearing an open toed shoe with a high heel even though she is quite tall to begin with. She makes it to my desk and I take my hand from my pocket as casually as I can. But she noticed.
"what are you doing, have you got something in your pocke..."
She stops mid-word. She has noticed that I have an erection. It is very obvious, as my pants are a light fabric and my cock is about to burst through them. I stare down at my biology book. I am in serious trouble.

Then her hand moves towards my penis. In front of the entire class. I am wondering if she thinks it's something else in my pocket and has not realised that it is my cock. She touches the outline of my cock briefly and gently. I almost blew my load into the fabric of my pocket. I am about to pass out with how fucking horny I am, how worried I am about my situation and how fucking confused and disoriented this has made me. She pulls her hand away, and pretends to look at something in her hand.
"Passing notes is not allowed in my classroom. I need to speak with you outside."

I have no idea what is going on. I can't stand up, My erect penis will be so obvious to everyone else in the class. She grabs me by the shoulder and pulls me out of my chair and towards the door. I walk out at a very brisk pace, hoping no one notices what is occuring in my trousers. She follows me out. I stand outside, and she is standing in front of me. We are about the same height and she is standing unusually close to me.