You try and hide your size

You google "how to fake a bulge" and discover the existence of soft dildo things called packers. You buy one from an online sex shop, as well as a penis extension sleeve. Once they arrive, you realise that the sleeve was a waste of time - the one you bought was clearly designed for someone with a longer and thicker dick than you, and won't stay on.

The packer is better. When you place it in the front of your pants and look in the mirror, it looks like you've got a large, semi-erect penis. The visual of yourself with a sizeable bulge excites you more than you expect. You rub the bulge over the fabric of your pants, imagining that it's real. You can almost feel it as you run your fingers along its length. As you stroke the bulge made by the packer, you feel your real penis harden. You close your eyes, picturing John stroking your bulge as you make out with him before you take out your huge dick and -

You gasp as you cum. The illusion is shattered as the tip of the packer stays dry while your micropenis coats the back of it in semen. Even though you're alone in your room, you feel embarrassed to have just cum in your pants from touching a fake dick. Still, having an actual bulge for once felt good, and the packer means that next time John reaches for your crotch, you won't have to worry about him being disappointed.

You head to John's place the next day with the packer back in your underwear. As it did the first time you wore the packer, the feeling of having a sizeable bulge turns you on, and between that and the promise of making out with John again, your little dick is rock hard before you even arrive at his door. Once you're inside, you can't help yourself, and you and John are making out on his couch within a few minutes. The decreased anxiety about your micropenis grants you a confidence you didn't have last time, and you don't shy away when he reaches down to feel your bulge.
"Whoa," John says, "you're kind of hung, huh?"
"You sound surprised," you grin. Your hands feel up his chest through his shirt, making him moan.
"I'm so wet right now," he says, "wanna feel?" You nod, and he takes your hand and guides it under his waistband and between his legs. As you feel the wetness of his pussy on your fingers, your inexperience catches up to you. What are you meant to do now? Your mind is a blank.
"You're really wet," you remark stupidly.
"Well, you really turn me on," he says, moving against your fingers. He grabs your packer bulge, stroking it. Hums of arousal rise from your throat, and you can feel the beginnings of an orgasm building. He slips down his sweatpants as you clumsily caress his pussy. You may have been able to solve your lack of a bulge for twenty-five dollars plus shipping, but faking experience is proving not to be such an easy fix. You just play with his pussy as the two of you make out, hoping that you're doing it right.

"Have you... done this before at all?" he asks after a short while, causing you to die a little inside. You panic, not knowing what to say. You don't want him to know that you're a virgin - what if he asks why?
"Done what?" you ask stupidly.
"Fingered someone with a vagina," he says. You're a little relieved. Theoretically, you and the big dick you're pretending to have could've had plenty of sex without ever touching a vagina.
"No," you say, "I've only ever touched dicks."
"Okay, so just think of my clit as a small dick and you'll do fine," he assures you. Shit!!! You've never touched a dick other than your own either! You think about all the times you've jerked off your micropenis. You've always tried to get it done as fast as possible, rubbing the little nub that is your micropenis quickly with your fingers. You try to replicate this motion on John's clit. It seems to translate pretty well, and to your relief and delight, John begins to moan. You grind your packer bulge against him as you rub his clit. Your tiny dick slides against the smooth and pliant back of the packer

You're so focused on what you're doing that you almost forget that the packer isn't part of you. When John reaches down and squeezes it, you feel your body respond as though he were touching your own dick, making you moan as you feel precum leak out, making the back of the packer slick and all the more pleasurable to press against. You're already fighting back an orgasm, but the knowledge that you can't take much more of this is pushed to the back of your mind by the more present desire to keep feeling what you're feeling. You ignore your body as it warns you that it's reached its limit, that it's going to burst.

Then, two things happen at once. You feel yourself reach the point of no return, and John hooks his fingers over your waistband and begins to pull your pants and underwear down.