You lay the condoms on your bed and push the box of condoms under your bed. Then you take off your t-shirt before removing your cargo shorts and shoes. You are soon standing in your white briefs and trying to decide on a condom. With a deep breath you begin to slowly lower your hand to a condom when your bedroom door opens.
"Hey Scott! Have you seen my...." Mark stops midsentence. You were currently faced from the door but you could imagine the face he had of shock in catching his younger brother in his underwear with a bunch of condoms. "Scott! What are you doing with those?" Mark shouts in surprise. He walks behind you having clearly noticed the condoms on the bed. You turn to face him and blush. You want to cover yourself but the only clothing on you were the white briefs currently.
You get a better picture of Mark now. He's shirtless with a towel wrapped around the waist. It seems he was just about to take a shower. He looks a lot more threatening now with the way he towered over you and his muscular physique. "I can explain" your voice cracks in fear. The last thing you expected was to be caught but you had absentmindedly forgotten to lock your door. You notice Mark's angry gaze focusing on you and realize that he was waiting for an answer and fast!
You stammer before you let out a lie "I was going to try jerking off for the first time". You're shocked at your response and so is Mark. "Wait! Then why do you need these?" He says pointing at the condoms on your bed. "A kid at school said you need condoms to jerk off so I got some from Dad's drawer" you continue to lie. Mark stares at you for a few seconds before laughing. "You don't need condoms to jerk off!" He says with a grin replacing the look of shock from before.
"Listen I can show you how to jerk off" Mark says with a mischievous smile and drops his towel revealing his dick. It's a bit smaller than your Dad's probably by an inch but a whole lot bigger than yours with balls to match! Its also surrounded by a bush of brown pubes and just as thick as your Dad's dick. You watch in surprise as he begins to walk to you and looks down at you. "I know this is your first time so I'll try to show you everything I know" Mark says confidently as if he was preparing to tutor you in a subject he had experience in. With a bit of hesitation you grab the band of your briefs and lower them to reveal your young prepubescent cock.
You look at Mark and realize how young you must appear and try to use your hands to cover your dick. "Don't be embarrassed" Mark says pushing you hands away. "One day you'll be as big as me promise" Mark says with a smile. You blush realizing how once you were older than Mark with a dick nearly as big as his but now appear as a young and undeveloped teen.
"OK first you want to get hard" Mark says and walks closer to you until your cocks were side by side. You can truly compare your sizes now and your dick looks like a joke next to Mark's. When you were Jay, your dick was about 7 inches soft, now it barely looks like 3 inches whereas Mark had a 6inch dick soft. The small halo of blonde pubes surrounding your dick didn't make you look any older either especially compared to the bush of brown pubes Mark had.
You looked at Mark who took his hand and began to encircle his dick before moving it up and down. "See just like this" he said confidently. You blush once more. It was so embarrassing to be "taught" how to masterbate by someone not only younger than you (in your original body) but in your current appearance as well. Compared to Mark, who's six-pack, body hair, and dick made you feel more adolescent than you truly were, appearing as a prepubescent teen was not something you currently enjoyed even more in the prescence of a more mature and developed teen.
You take your hand and pretend to mimic Mark as if you were new to the entire process however you were having a hard time getting hard. You decided to think of something attractive and close your eyes but to no avail your small thin cock stays soft. You open your eyes and look at Mark, whose cock had become erect, and you feel a twinge in your dick as it begins to grow hard. You shudder realizing you were finding interest in Mark, and you had to admit he was kinda hot. But you weren't gay! After all, you dated plenty of girls in your original body but your previous experience as Jay seemed to have had changed you.
"Good job little bro" Mark says spotting your erection. You hope your red face wasn't too obvious but the both of you continue to jerk together. "OK little brother, when you feel a sensation coming that's when you know you're going to climax" Mark explains and begins to moan in pleasure as precum leaks from his dick. You watch in surprise as he starts to increase the speed on his dick. Watching Mark makes yoj feel more horny and soon you were so close to cumming.
Mark then moans as he cums and shoots layers of cum while you watch feeling more and more horny. "I don't expect you to cum this much little bro but since this is your first time I'm kinda curious to see how much you release" Mark says. You frown and begin to become enraged. You were kinda getting tired of Mark treating you as a young and inexperienced teen, but technically from his perspective he saw you as his little brother.
Nevertheless you still feel a bit annoyed, as you continue to slide your hand over your cock you feel the slight sensation building up. You look as your thin and small erect cock begins to leak more precum in preparation. And just as you were about to cum....