It irks her that Gamora is still her better when they spar. She is hard and fast and feels no pain to hold her back; Nebula can afford to be vicious in a way that is beyond the means of most creatures, and certainly her sister. And yet Gamora had bested her once more.
Perhaps that is why now she takes great pleasure in looking over the inky blacks staining and spreading beneath Gamora’s skin while she clicks her limbs back into alignment and adjusts a few wires. Unlike her, Gamora moves gingerly, as if she is more fragile than anything else would indicate. It is both fascinating and infuriating.
Even after Nebula has finished with her maintenance, Gamora still sits stiffly, holding the bones of her wrist in place so they fuse together correctly in the coming minutes. Her body is imperfect. It needs to be coaxed and cajoled rather than snapping back into place effortlessly. And this healing does seem to cost her sister.
Nebula moves closer and reaches out for her. She extends a finger and places it over one of the bruises she left on her sister’s skin, prodding it roughly until a hiss escapes from between Gamora’s clenched teeth.
“Stop that!” Gamora protests, but Nebula pays her no mind. She selects another bruise and worries it similarly.
Her sister doesn’t stop her.
Nebula has always wondered - too long past since she would have experienced it for herself - if the reaction is not unlike when the exposed tips of broken wires come into contact with each other in her arm and cause her fingers to twitch. She jabs the bruises she left behind on her sister and watches as Gamora’s jaw tenses, her muscles clenching, the cascade of little nuanced actions that would suggest a mechanical reaction if only they were ever the same.
It is only the knowledge that pain is an unpleasant sensation that Nebula continues to allow it to her sister when she cannot experience it in turn. She is not envious of the way Gamora tries to squirm away from her prodding fingers, her lips parted around some noise of displeasure that looks and sounds perhaps more enticing than it was intended. No, Nebula is not jealous of their father’s favorite. The one he allowed to feel, with all of her contradictory reactions.
There is seemingly no rhyme or reason to it. Gamora acts differently to every touch; never the same no matter how consistent Nebula keeps the location or the force and pressure. “Your programming is faulty, sister.”
Sister, enemy - of course she would exploit that. Gamora swats her hand away, scowling. “I bested you.”
“Next time I won’t fight fairly.” Nebula warns her. Pain is barely a distraction to Gamora. Whatever else Nebula could say about her sister, she is well trained. But Nebula also knows she can do things to Gamora that don’t cause her pain and somehow distract her all the more. She demonstrates that now, leaning over to trail her fingers up the inside of Gamora’s thigh, skirting around the bruises she’d left this time.
Her sister reacts the way Nebula knew she would, spreading her legs further and leaning back - as if to encourage Nebula to continue. And she wants to. It is a heady thing to make Gamora’s body react to her in new and strange ways, to search out every exploitable point and glitch, but Nebula halts, her hand lingering at the top of Gamora’s leg. If she is to truly claim victory, Nebula wants for Gamora to play a part in her own undoing. It makes it that much more enjoyable.
Gamora stares her down. “I know what game you’re playing, Nebula.”
“Do you?” She taps her fingers against Gamora’s flesh, warm beneath the sensors in the tips. A little bit higher and she brushes over the outer lips of Gamora’s cunt. It’s even warmer, and makes Gamora’s whole body shudder when touched so gently. Her mouth parts, lips wet from her tongue.
Nebula ignores her, or pretends to, moving her hand away.
Gamora flings a leg over her before Nebula can react, trapping her beneath her sister. She could throw her off - thinks about how lovely the crunch of Gamora’s bones would sound if Nebula were to throw her through the far wall - but she might not win that ensuing fight. Better to disgrace Gamora more reliably.
“Damn you, touch me,” she growls. Clearly her sister agrees.
Nebula grabs her by the hair and yanks her head back, leaning forward to bite her neck. She will leave more bruises on Gamora, ones that for no explainable reason Gamora seems to enjoy, but that provoke their father’s irritation to see.
When Gamora’s hands clench around the top of her thighs, Nebula can calculate a great deal of force from her grip and strengthens her bite to match. It drags noises from her sister like howls and causes her fingers to curl further, but Gamora doesn’t attack her for it. Frustrating, fascinating.
Her clothes, what little of them she wears, shred beneath Nebula’s other hand. The electricity sparking in the palm of her hand and traveling down her fingers might help, and the burnt-fabric smell corroborates that, but it was not her intention. The way Gamora shrieks when Nebula touches it to her skin though, is. Her thighs tense around Nebula’s then too and the play of muscle is both exciting and beautiful to her, so unlike the force and lock of her own mechanical parts.
Nebula wants to make her sister feel the way she’s never quite managed before. She wants to tear Gamora limb from limb - but dad wouldn’t be pleased.
She settles for the next best thing and switches off her electrical current before plunging her fingers into Gamora’s body. Once she hadn’t. It had been delightful, but Gamora had refused to speak to her, or go anywhere near Nebula for weeks after. Nebula had been more irritated by her sulking than her hatred, and so vowed not to do it again.
It's near satisfying enough to hear her sister exhale like she's been kicked in the gut, her hips jerking against Nebula's hand. From the quick, jerky snap of them Nebula would assume pain, but she knows well enough from past experimentation that it's wishful thinking. Still. If she can break her sister - so much more perfect than Nebula with all of her imperfections, so much more beloved by their awful father - she'll have it by pain or by pleasure, or any other way she might manage.
Nebula curls her fingers, dragging the tips down Gamora's insides as she shoves them in and out of her cunt. Her sister is too well lubricated for it to pain her much, and the force insignificant, but that doesn't stop Nebula from imagining how similar it might feel to disembowel her instead. She licks her lips at the fantasy, and as fatally distracted as she's made Gamora, her sister takes it as a sign of pleasure.
It matters not that their father has forbidden her such maddening sensation. Not when Gamora bends her head to kiss Nebula in response, making uncharacteristically soft noises against her mouth. Nebula's world is reduced to awareness of the sensors in her fingertips and mouth, and the wet noises Gamora's body makes. She's beginning to tighten, muscles squeezing around Nebula's fingers not unlike the spastic contractions caused by a misfiring circuit.
"Harder," Gamora nearly growls, and Nebula is amused enough not to remind her sister that biting down on her lip is no different than attempting to pinch any other part of her body. She breaks away long enough to locate the place on Gamora's side just high enough for the bruises she's planning to leave to be seen, and Nebula grabs her there. The stained flesh will look even darker through the mesh of her clothing - irrefutable proof that Nebula has bested her, on display for everyone to see.
"You're pushy," Nebula scolds, tightening her grip against the rock of Gamora's hips - always making things more difficult for her - "It's insufferable."
"As are you, sister."
Her scowl doesn't last nearly long enough. Nebula takes pleasure in stealing it from her with a particularly harsh jab of her fingers, and the sound Gamora makes in response feels like it should set something off within her mechanics like a particularly harsh catalyst. Gamora rolls her hips once more, cunt tightening like a vice around Nebula's fingers while the signal loops out to the clench of her hands and thighs. It's all heat and pressure against Nebula's body: pleasurable in it's own way, yet wholly different from the satisfaction of Gamora's undoing.
She shudders, and comes with something close to a scream that reminds Nebula of death. The good kind of death: messy and bloody beneath her hands, watching first the spark of fear and then pain before the awareness fades from their eyes. Gamora's slam shut, but maybe one day.
Yes, Nebula thinks. One day, when this ceases to amuse her, when she is no longer equally fascinated by her sister as she is frustrated, in awe as she is bitterly envious. She licks the fluid from her fingers and listens to Gamora's labored panting, imagines how beautiful she'd look injured at Nebula's feet, unable to fight on. Gamora would never beg for her life, and Nebula would not spare her for anything less.
Knowingly or not, their father set them on this path: tension and friction sparking over and over again until one of them will eventually destroy the other, and Nebula wouldn't have it another way. Because only she deserves to murder her sister - utterly too captivating, her greatest adversary and closest companion. No other creature should ever have the privilege.
One day, but not today.