Do it

Alright, you start taking your clothes off. One by one. What makes it even worse is that she keeps looking at you the whole time, paying close attention to your body and what you look like. She even keeps smiling the whole time as if she isn't aware of the fact that being naked in front of your teacher is quite a weird feeling that you don't have every day.
"Take your time, Tim."
You stop as soon as you have only your underwear left. You can't take it off, not when she is looking at you like this. She is scrutinizing you, watching you so closely. You keep waiting for a few moments hoping she might tell you to stop. But no, she is really expecting you to take off everything. You go ahead, with no other choice but to comply. You take your underwear and push it all the way down, your semi erect cock slightly springing up in the process.
Rebecca smiles. "Very good, Tim."
You instinctively try to hide your semi hard-on, but she obviously doesn't like that.
"Oh, please keep your hands to the side. There is no need to hide something from me, you can trust me, Tim."
You reluctantly comply and keep your hands to your sides.
"Sit down right here."
You slowly sit down into the leather chair, the leather feels a tad cold underneath your bare skin.
"Now, let's just talk about you and your problems. This is much better now that you're naked, right?'
"Uhm, well, to be honest...."
Your cock grows even harder.
She smiles. "You are getting erect. No need to panic, Tim. This is natural. Please try to sit on your hands so you stop the urge to cover up."
You try her advice and sit on your hands. It feels more than strange to sit right in front of Rebecca with your cock right there completely exposed to her, standing up rock hard while she is staring at it.
"This is good. Now have you and your sister been fighting often or only recently?"
Seriously, does she expect me to talk about my problems like this?
"You look uncomfortable, is there anything else you would like to do now?" She eyes your cock. "Would you like to do something about your cock?"
You look at her confused.
"Wait, let me take care." She bow forward and puts her hands on your hard on, starting to move up and down! What is happening? She can't be doing this, now can she?
You feel good, very good even. She is starting to stroke with faster pace, prompting you to start moaning.
"Good, Tim, let it all out for me."
Oh my gosh! you think as she goes faster and faster. After a while, sooner than you thought, you're beginning to get close, You moan even more, ready to burst...
She lets go!
What?
She leans back again and watches you, your hands are still under your bottom, and so your semen is flowing out of you slowly, your cock twitching around. You keep shaking until your ruined orgasm has ebbed off.
"Why did you stop?" you ask confused.
"Because I think it is better for you when your penis cums on its own, by its own strength and will. I always do it this way. you will learn that this is the only way men should have an orgasm. I'm rather strict when it comes to this matter. I'm sorry if this was confusing for you."
"Oh." You say, still a bit confused, .

Five minutes later you're back out in the corridor.