Jake is going to fuck you.

You walk up to the side of the bed, unable to take your eyes off of his cock.

He pats his thigh, saying "Sit right here. Don't put it in you just yet. Just... Sit."
You rest a knee beside his leg and swing your other leg over his. With a leg on either side of him, Your basically sitting on his knees. But then, he grabs your ass and pulls you closer to his erection. You can feel the heat of it resting against your abs, occasionally bobbing a little just to remind you it's there.
Looking down, your greeted with a sight that you haven't seen in some time. Namely, the sight of a cock sticking out between your legs. Of course, this cock doesn't belong to you but the nostalgia is nice all the same.

Jake reaches up and places his hands on your hips.
"How does it feel?" He says, running his hands along your thighs. "To be right there. Staring at it. Knowing that it will be inside you?"
Your breathing gets heavier. "It's... hot."
"Oh?"
"I meant it literally. It's fuckin' freezing in this place and the only real heat I've felt in a while is those clothes and... you."
"Interesting. I should take notes. Doctor Reynolds would be very interested to hear this."
"Don't talk about that freak right now, I'm-"
You stop mid-sentence when Jake's thumb reaches between your legs, pressing on the top of your pussy. A wave of pleasure washes over you. It feels so foreign to you after having been used for pleasure for the past few weeks. You have to put a hand on Jake's chest, just to brace yourself and not fall over.
"Mnh, What the, ah, fuck are you doing!" You say, taking all of your willpower not to moan.
Jake says, "This is your clit. From what I understand, it's a pleasure center on a woman's body."
His thumb makes tiny circles, rubbing at the little nub on your body.
"I'm getting you ready. I thought that, for your first time, I would do a little foreplay. You should be glad you get to feel this, you won't always have time to prepare yourself."
But then he stops. And, god help you, you miss it. The pleasure was intoxicating. You would never admit it to him, god no. But still.

"Now what?" You say between breaths.
"Now, you're going to sit up and put me in you. You're going to ride me." He says.
"But, I'm not going to command you to do it. I'm just going to ask you nicely."
You say, "And if I don't?"
"I'll command you to do something else. You won't like that as much." He says back.
Great.
You sit up a little. Inching forward, you glance down. You are positioned right over him right now. Reaching down, you grab hold of his shaft and aim it properly. Then, you slowly bring down your ass onto his dick. You can feel it enter you, crawling inch by inch up into you. It feels like its splitting you apart.
You stop half way through, stammering out, "No, no, I can't, this is, I don't-"
Hands still on your hips, Jake forces you down the rest of the way, hilting himself in you. You feel a flash of pleasure, the **** of your first female orgasm making you feel faint.

"AHN!" A loud moan forces itself through your lips.
Jake is grinning from ear to ear. "Did you just cum?"
You're actually blushing right now. You've never been so embarrassed in your life.
"No, I didn't."
"Yes you did."
"No. Shut up."
"Admit it. You came just from that."
You cover your face in shame, hoping in vain that might stop this from happening.
"Yeah, okay! Of course I did! You shoved your whole dirty dick in me! Fucking asshole..."
"Don't give me any ideas..." He says.

You start to say, "Well, I hope your fuckin' happ-" when he cuts you off again by thrusting up into you.
"You have no idea how happy I am."