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Eyes averting.
Biting lips shut.
Legs shaking.
Dick Grayson’s pleasure is completely under her control.
Cassandra Cain knew she was soft. Her mother, Lady Shiva, always reminded her of that weakness. Besides Batman, Dick was among the few men who saw that and accepted that part of her. His brotherly affection was unique and special to her. It was as if he was both Batman and Robin at the same time. He would ruffle her hair then rest his hand there. While Damian hated that and would murmur, she likes it. He was always bright with a shadow inside him while she was the opposite. For all the darkness she carried, she was soft.
Cassandra knew of her adopted brother’s reputation. During missions with other superheroines, gossips of his prowess in bed was bound to be a topic if not an inside joke. Before she could even learn to string sentences together, one was already on her tongue, “Nightwing is a slut.” In their world, muscle bound men are commonplace. That was not what kept Nightwing in her mind. His warm smile and heartfelt words always oppose the sex fiend picture that her colleagues talk about. She has seen him flirt, yet be physical like that is not inconceivable… but weird.
After a bad night, Dick was sore and exhausted. What was supposed to be a bike ride from Bludhaven to Gotham turned to a battle one after another. Unrelated incidents from snatching to break ins littered the way back to the Manor. His adopted father sat on his usual chair in front of the batcomputer.
“Hey Bruce, why was the way here hellish more than usual?” Dick asked in his usual flair as he dismounted his bike.
“A crime spree caused by a black-market app rewarding users per crime they commit. It has been only been up two days but the uptick is noticeable. I’ve had Tim and Barbara check its origin. Damian and Jason are already out there on patrol.” The Batman replied.
“Hah! Them together?” Nightwing chuckled in amusement.
“They split fifteen minutes in. I will join Damian now.” Batman admitted defeatedly as he stood up.
“I will nap for an hour or two and I will join you in patrol.” He said as he has removed his uniform.
A rough grunt of affirmation came out of the dark knight as he rushed to the batmobile. The engine’s rumble quickly vanished out of the cave. He made his way up the manor to his room.
He went through his usual motions, brushing his teeth, facial, then… a creak from the floor echoed in his ever-vigilant ear. He slowly got out of the bathroom. His adopted sister, Cassandra Cain stood on the doorway of his room.
“Jeez Cass you scared me. I heard you were out of Gotham. Wanna catch me up on what you’ve been up to?”
Cassandra stood motionless with a blank stare on her face.
“Are you ok?” Dick asked with a concerned look on his face.
“Nightwing is a slut.” She uttered matter of factly.
“Ouch! Haha! Hey don’t slut shame me sis.” Feigning hurt, he joked.
In a flash, she was in front of him. A hard push sent him backwards to his bed. He rolled backwards to face his adopted sibling. His body instinctually went to a fighting stance.
“Do you really think you will win?” His assailant asked.
A wave of uncertainty washed over him. ‘Is she mind controlled? Has anyone put her up to this? Do I actually have a chance of subduing her?’
A sharp pain in his liver shocked him back to reality. He threw a wild cross and felt a trip a second too late, as he was on his back and she was on top of him. A spray from her wrist to his face, he held his breath. A butt slam with Cassandra’s whole weight on his stomach made him suck in air. A familiar sweet taste of Ivy’s pollen flooded his lungs.
“Why Cass?” was all he could say as he felt his body weaken and grow hotter.
A film she watched on her phone introduced a word she was not familiar with, taboo. A night of film depicting a ‘taboo’ act of sex with your brother, awakened something inside her and she liked it. She might have no blood siblings, but she had an entire family with the bats. It was immediate to her, Nightwing, was who she imagined. His warm and gentle smile that shone in the darkest times. She considered him family, but imagining Dick’s embrace made her grind her clothed clit on her pillow. She felt a warmth she has never felt for anyone before. ‘Taboo’ felt like the right word, and if the videos are of any guide she needs to show him.
As if a gift a few days later, Dick came back from Bludhaven.
Stiff shoulder
Bruised ribs
He was weakened.
Sneaking a vial of Ivy’s sex pollens and a wrist mounted dispenser, she made her way to her brother’s room. Water rushes from the faucet and she stood in the doorway thinking of what she wants to do. She knows of her brother’s experience of being taken by force and being helpless. She noticed, in cases of rape and sexual assault, Dick was more spirited in delivering the criminals to justice. She looked down at the spray on her wrist and stepped back. A creak from the floor made the acrobat pop out of the bathroom. Her older brother was down to his black boxer with an obvious bulge of his infamous member. He said something but his smile reminded her of what she wants, taboo.
Dick was a mess, breathing heavily with sensitivity heightened. Cassandra made sure that the pollen has taken effect and eased her weight on her brother. The acrobat tried to move but his body won’t heed. Sure that her brother can’t escape, she looked at his crotch. His cock was fully hardened, struggling against the fabric of the boxers. The assassin went low, cupping his balls through the boxers. The touch continued to eager groping then languid strokes.
“Cass, stop.” His protest was weak and pathetic, a departure from the strong and confident Nightwing. ‘Not again! I can’t be this helpless again.’ His mind can only protest inside.
‘Gagging is not necessary. I want to hear him too.’ She thought as her hand firmly gripped his shaft through the fabric.
“You like sex, don’t you? Enjoy.” Words that the acrobat never imagined coming from her of all people.
Cassandra continued to stroke his clothed shaft. ‘I’m not like my father. I do not want to have a child. I just want to enjoy Dick’s company, like others have.’ Then she felt it, her older brother’s own weak thrust chasing her hand. “I am glad you like this.”
Dick closed his eyes as her fingers released his cock and played with the hem of his boxers. The reduced resistance of his boxer on his cock meant that his boxers were being pulled down. A cold chill on his cock meant he was exposed, throbbing hard and exposed. Just then a warm wet sensation crawled down from his tip down stopping midway. In fear of the worst, he opened his eyes to see his adopted sister’s foreign eyes locking gazes with his as she tried to go deeper. Her small stature seemed like a mismatch to his sizable member. Her tight mouth got wetter with her saliva as she tried to go deeper. His tip was poking the back of mouth and the entrance of her throat. The silent assassin relaxed her throat and welcomed the warm hard cock. Like instinct from his multiple experiences, he slowly pushed in his cock further inside her.
A loud gag then a cough came out of Cassandra. She immediately pulled her head up, releasing her victim’s cock with a wet pop and a coating of bubbling spit. She wiped the saliva off her lips and used the same hand to stroke to stroke Nightwing’s glistening dick.
“I knew you will like it too. You are a slut, Dick. Barbara, Zatanna, Dinah, everyone knows you are!” She exclaimed as she gipped him harder.
Except, Cassandra didn’t see the same warm smile she had hoped to see. She saw tears and an unimaginable face on her brother. Fear? Disgust? Lust? Either way she knew, she caused it.
“Please, fuck me Cass.” Dick softly moaned a plea. He begged his assailant for more.
Cassandra’s lips were closed tight, and her chest rose and fell quickly. She climbed up and stood on the bed, with Dick’s crotch in the between her legs. He saw a wet spot in the middle of her black yoga pants with an obvious outline of his sister’s cunt. She slowly pulled down her tight pants, avoiding looking at her brother’s focused eyes. Still, she felt the hard stare taking in the sight of her wet pussy, curvy hips, well defined thighs. As she removed her pants completely, she tossed it at his face, hoping it hides her next actions. She squatted down placing her dripping wet pussy lips on his shaft. Grayson can’t help but whimper at the wetness against him while the strong smell of Cass’ sweat and lust filled his nose. A thrust of her hip, slid her wet cunt up the long shaft. She humped her adopted brother’s cock like the pillows she sought relief with. The shaft slid against the length of her cunt to her clit. Both groaned at the newfound sensation climbing up their spine. Wet squelching, mixing sloppy blowjob spit with rabid humping wetness, filled their ears. In a motion, both of Cassandra speeding up her grinding and Dick seeking his own friction, the tip of his cock slid inside her wet tight pussy.
One smooth motion, lubricated by her fluids and forced by both their needs, Grayson found himself penetrating Cassandra. The Black Bat yelped at the new object in her, stretching her out. She slowly lowered herself with her hand on her brother’s waist, every slow inch squelching in her wet cunt. She has fingered and used improvised dildos but nothing as warm, big, or even as enticing as her older brother’s cock. One last grunt and he was fully hilted inside her. She bit her lips trying not to moan louder than the man beneath her. She tried rising but the friction of his tip rubbing deep inside her made her legs clamp shut. Gasping for air, her mouth shot open. Then a jolt, Dick, chasing his own pleasure, slammed his hip to her plump ass.
“You think… you can rape me and not fuck me properly?” Dick gritted his teeth, feeling his strength return to him. His hands weakly grabbed Cass’ hips, and slowly pulled his cock out. Half way out, his slick coated cock rammed back in with a hungry vengeance. He felt a pang of guilt as he reciprocated the hunger his adopted younger sister showed him.
Black Bat’s eyes rolled the back of her head, feeling the sheer length and girth of her adopted brother’s infamous cock in action. Each thrust, earned a moan and wet squelching from her.
“~AH~YES! F~ah~ck me, Dick! Fuck me, slut!” Through heavy breaths and moans she commanded her stud.
“We’ve got a lot to talk about after this but if this is what you want.” Dick warned.
Just as Dick tried to further his control, Cassandra grabbed his wrists and pinned them above his head. She forced her hips easily down his cock with her creaming wet cunt. This time she won’t relent anymore. Each slam of her ass to his thighs is her chasing her own climax. His cock stretched her tight pussy unlike anything she had felt before. She focused her sights on her prey.
Eyes averting.
Biting lips shut.
Legs shaking.
The acrobat was lost in lust like her. Each motion was more frantic than the last. She tightened her grip on his wrists as she felt the climax building inside her. His back arched, cock reaching deeper inside her every pound.
“Pl-please Cass I’m going t-to cum.” His begging came weak and needy.
Cassandra leaned in to whisper. “Cum inside me, Dick. I am on birth control.”
She left a kiss on his sweating neck. She let herself be taken by every wave of pleasure electrifying her spine. Wet sloppy cunt tightened with every fucking she was taking. A kiss planted on her cheeks made her clench tighter as the pressure inside her blows. She squealed with lust coating her exclamation. Her legs shook and her pussy squirted all over Dick’s member. The newly found tightness and wetness pushed the acrobat to the edge and shot is warm semen inside his adopted sister. She collapsed on his bare chest, heaving from the intense climax. They spend a few minutes in silence, save for their exhausted breathing. The responsible older brother broke the silence.
“What was that? mind control?” Dick tried to puzzle Cassandra’s bizarre behavior.
“Learned new word, taboo. Thought of you.” She replied with a hint of regret. She nuzzled deeper in the arms of the man she attacked. But instead of scorn or rage, he held her tight.
“You could have just talked to me about it. I’m disappointed but I understand that these emotions are difficult on you. Take your time to understand them and I’ll be here for you.” His hand brushed her hair in the old familiar tender way he does.
Cass looked up to see that smile, that damned warm smile. Chasing his light, she thought she wanted him that way, that carnal and animalistic way others do. As she laid on top of him after having done the worst sin, she realized she wanted him like no other woman does, like family, like a brother. Her hands trembled in fear she couldn’t understand, but she knows she caused it.