"C'mon Sonata, it'll be quick."
>You say, your voice barely a whisper above the sound of the packed train grinding along its tracks
>"Anoooonnnnn, I don't wanna. Not with all these people here." Pleads your little sister.
"Pleeease Sonata? Do it for your big brother?"
>Sonata gives you a pouty frown.
>"Okay. But be quick, I don't wanna get caught!"
"Thanks Sis, you're the best."
>All you get is a resigned huff in response.
>Your sibling and yourself slowly reposition until you're both tucked into the corner of the transit car, Sonata pressed face first into the wall of vehicle.
>"Hurry up!" She hisses at you.
>Heeding her words you quickly reach for you fly and pull the zipper down before fishing your cock from its fabric jail cell.
>You hear Sonata's breath hitch as your shaft presses against her backside.
>Your less than enthusiastic sister quickly reaches down and pulls her panties to the side, before pushing her hips towards you.
>"Get it over with already."
"Okay, okay geez."
>Gently raising her skirt you gain access to your sibling's tender womanhood, your aching member straining in its presence.
>Unceremoniously you push into her delicate folds, Sonata's lower lips parting for the throbbing cock that was now burying itself into her.
>Grunting you put more of your weight into her and force yourself to the hilt in your little sister eliciting a soft moan from the blue haired girl.
>You withdraw your cock quickly before once again stuffing it into its rightful place within Sonata's warm depths, your return stroke forcing another soft moan from her lips.
>You begin thrusting at a steady pace, each time you hilt forcing Sonata against the wall.
>Your stealthy fucking continues for several minutes, each time your wet shaft meets the cool air of the train car it only increases your desire to plunge it back into your sister's tight hole.
>As Sonata and you continue your coupling a familiar urge begins rising up in your loins.
>"Anon, hurry up! Our stop is only two stations away!" She whines.
"I'm almost there Sis."
>You grunt.
"Can I cum inside?"
>Sonata shakes her head.
>"N-no, it's not s-safe today." She says, struggling to get the words out as you bury yourself into her again.
>You feel her hand graze your testes.
>"J-just finish in my h-hand so you don't leave a mess."
>You grunt in affirmation as you redouble your efforts.
>Faster than before your member impales your cyan sibling, her hot inner walls coaxing you to the edge with each powerful stoke taking your shaft within spitting distance of Sonata's womb.
"Fuck, I'm gonna cum!"
>You hiss into her ear.
>"In my hand Anon!" She replies
>You begin pulling out, preparing to splatter the contents of your balls into her dainty hands just in time for the train to engage the brakes.
>The sudden deceleration throws you and sonata forwards into the wall, and forces your cock as deep as it can go within her honeypot.
>Unable to stem the tide your orgasm hits you full force and your engorged phallus shoots rope upon rope of alabaster seed against Sonata's cervix.
>Like a man possessed you spasm with each shot, the pleasure of heaving your load into your sister's snatch overriding your self control until your orgasm abates.
>The train starts moving again as you pull yourself out of Sonata.
>"Anon! You weren't supposed to do that!" She squeals."
"Fuck! I couldn't stop it, it was the train's fault."
>You say as you return your spent member to your pants.
>Sonata says nothing as she puts her panties and skirt back in place.
"Our stop is next, when we get home you can wash it out."
>"..."
"Shit, I'm really sorry 'Nata."
>Sonata gives you a sad frown
"I love you sis..."
>"I love you too..."