With a pronounced swish, you finish the black 'e' of the oversized 'Transfem Pride' poster you'll be crowding the other bus passengers with when you drag your big sister to her first pride parade. You look over at her, ready to mock her with the fact that she gave in after years of calling it 'too commercialized to bother with', but before your tongue finds a taunt, you notice a big dot of pink ink on her lower lip. She's still trying to think of what to put on her poster, and after a few moments her bottom lip falls open, and she starts to tap the tip of her thick pink sharpie on it while she thinks.
The moisture on her lip glistens in the white light of the kitchen, and try as you might, you can't stop staring as your mind starts to wander. You can see her lips opening wider, and she keeps tapping as her tongue slips further and further out with each touch, curving little by little to cup the tip of the pen more perfectly, and you can feel your cheeks start to grow warm as a pressure builds between your legs.
Reality flickers in for a moment when she makes that kind of grunting sound she always does when she's trying and failing to be clever, and the end of the sharpie starts to trace back and forth across her bottom lip. The image finally comes together in vivid detail, and her wet lips are tenderly caressing the tip of your cock, slick and smooth, light kisses turning more emphatic, little touches of suction as she starts to make out with your sex more and more, hands coming up to keep you in place for her to worship you with her mouth.
You squirm in your chair a little and idly adjust your panties to constrict you a little less while you stare and imagine. She hums open mouthed as she stares down at the paper, tapping the pink felt against her open bottom lip harder, and it's you, hand on your shaft to tap your tip on her lips, hearing the little moist noises and feeling the wetness she's given you. Your face crinkles as you look down at her intense eyes, waiting to see her give you permission to put it in her mouth, hearing a little hum as she nods a half inch and opens wide. Your heart blisters with disbelieving adrenaline as you slide in, feelingā¦
You flinch and blink your eyes quickly to return to the moment, and your sister is standing in front of you and loudly snapping her fingers in front of your eyes, once, twice, four more times even after you've obviously already refocused on her. "Are you even listening?"
You have at least a dozen IQ points that didn't just drown in your arousal. "What? Yes, obviously. You just need to do the highlights, I already got the outlines."
Hearing her be mean to you boils that familiar little feeling in your chest that you didn't understand until you hit puberty, and you squirm in your chair a little. Your previous adjustment to your underwear stayed too tight while your sister's big lips sneered at you, and you're⦠totally still staring right at her lips and not her eyes. But after a moment's abject failure to refocus, she reaches out and grabs your lower lip with two fingers, disdain evident on her face. "You got marker all over your lips!"
The black sharpie in your hand clatters out of your fingers onto the table, and you try to look down to see what kind of mess you made, but she keeps a tight and painful grip on your lip. You whimper a little, and she laughs at you, exactly the sound that you loathed growing up, right up until she came out and it started to make you feel weird in ways you didn't quite understand.
She finally releases your lip with an upward yank, but then she quickly catches your cheeks with the same hand like a juggler and squishes your mouth open.
"Wh-whatreyou" Your squished question muffles out of existence as you stare upwards, watching her eyes locked on your lips. Your face is getting hot and hazy and your pants are getting very tight, and it'll be a very awkward risk if you have to stand up from the table in front of her any time soon. It shouldn't turn you on to hear her say "You got it all over your tongue!" with as much disgust as she ladles into it, but you're a stupid teen and she's your stupid big sister.
As the horny brainrot starts to decay your focus more and more, you can feel your mouth watering, watering for her, and your hand strays to your crotch under the table as your mind starts to see her a few feet above you instead, you on your knees below, watching her slowly slide her panties down over her bulge with one hand, exposing the cock that you've been trying not to eye too much while she walks around the house in just a shirt and underwear.
You can feel her staring at you, but you can't see anything but her sex, cotton pulling away to let it free. Not quite hard, just enough to tell you that she wants your mouth, that she wants you to lean forward and wrap your lips around her, just the tip at first, taking your time to savor every centimeter, sucking gently, swirling your tongue around her more and more. You can feel her slowly growing harder in your mouth, getting closer to the perfect fit that you've shamefully craved since she invited you into the pool changing room after you came out a year later than her.
You pull back to lap at her, wet tongue caressing the sweet of her precum, savoring the taste and the way it lubricates your lips. She runs out of patience and holds your mouth open with one hand, the other guiding her sex right over your smooth tongue, the path slickened for her to smoothly hilt in your mouth.
She makes that groan, that one you heard through the cracked bathroom door when she was in the shower, the one that replayed in your head every time you watched TV with her and forced you to pull a blanket over yourself to hide how much of a creep you are for getting hard just from being in the room with her.
Your hands start to rub yourself through your panties, and her words are low, smoky ambrosia as she mutters "Fuck, youā¦"
They suddenly kick up in tone. "You're drooling all over!"
Your eyes snap back into focus and you're almost dizzy for a moment as you're rubber-banded back into reality. She releases your mouth, and when you close it you can immediately feel that she was right, that your chin is wet, and you flick a glance down at the table under you to see a little pool of saliva. There's too much for it to have just been a few moments, and you look back up at your sister to see her gripping her uncapped pink sharpie tight, cheeks flushed, eyes antsy and dying to dart away from your gaze, but she holds eye contact as she shakes her hand off. She stammers out "Fucking⦠fucking gross. You loser. Go like, clean up or somethingā¦"
Embarrassing as soaking the table might be, your hardness could probably cut a diamond right now, and you'd probably drop dead if she saw how stiff you got just from her holding your mouth open and staring at you. You glance away and stammer, equally clumsily "Uh, just, um just a minuteā¦"
When you look back she can't meet your eyes, and she turns away to pluck a few tissues out of a nearby box to throw at you. "Whatever⦠weirdo." She flicks a glance back at you, redder than ever, then she abruptly starts to move toward the door. "I'll be back later, to uh, finish." Her voice turns flustered. "I'll come back and finish your poster later!"
She shuts the door just a little too hard behind her, and as you dab at the drool on the table, your mind starts to drift again, wondering if she'll need any help finishing...