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Bad Brother AU

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Sans stared up at Papyrus, eyesockets brimming with tears as he shook lightly from underneath him, cradling his broken wrist gingerly.


His brother really was adorable.


“Shh, Sans. I’m not going to hurt you.” The smaller seemed to tremble even harder at those words if it were possible. He could sense his brother’s confusion, his terror, the hopelessness he felt. He wanted more of it.


Papyrus reached down from where he was pinning Sans down, and twisted Sans’ hurt wrist further. The reaction was instantaneous, uncontrolled-not that that was an excuse. Sans jerked away, breathing harsh as he gasped weakly. His chains clinked together, Sans cringing at the noise of rusty metal.


A brief flare of anger pushed its way to the surface, and Papyrus grabbed his little brother’s throat, choking him with his collar as he smiled inwardly in satisfaction, the latter freezing.


“Haven’t I taught you not to flinch away from me? Do you need more training?” Papyrus hissed vindictively, savagely pleased as more tears streaked their way down Sans’ face.


“m-m sorry...”


“You know by now that ‘sorry’ isn’t good enough. Apologise properly.” The older ordered, sitting up and pushing Sans off and onto the floor with a soft thump.


Sans whined softly, but reluctantly obeyed, crawling in between Papyrus’s legs with an empty kind of resignment that thrilled Papyrus right down to the bone. His brother was just so cute, sitting in between his legs, still silently crying as he struggled to unzip Papyrus’s fly.


He wanted to make Sans hurt.


He growled impatiently as Sans finally managed to pull his pants off, the smaller skeleton staring at his cock with both disgusted facination and a terrified hollowness. He grabbed the back of Sans’ skull, enjoying how the sentry gave a full-body shudder at the contact.


Sharpened claws dug into bone as Sans whimpered quietly, a low but beautiful sound to Papyrus.


“Get to work.” With a quiet sob, the younger leaned in, giving the head a little, hesitant kitten lick before reluctantly taking it in his mouth, the skeleton almost immediately grimacing at the musky, heady scent.


“Good boy. Take it deeper.” Sans struggled to obey, his magic reacting as it formed a lightly shimmering throat, Papyrus sighing in contentment as his member was wrapped in a warm, tight channel.


Papyrus sighed with a roll of his eyesockets as he suddenly pressed Sans’s head closer, Sans whimpering in alarm and shock as he began coughing wetly under the pressure.


“Sans. Suck or I’ll use your pussy instead.” The younger visibly shook at the threat, attempting to hold back his pained sobs as he began to deepthroat Papyrus, bobbing his head slowly but surely in the way he had slowly learned Papyrus liked over the course of three years that he had spent being broken in by his brother, shaped into the perfect pet that would satisfy all of Papyrus’s sadistic needs perfectly.


“There you go, slut. If you don’t get me off in five minutes, you’re not getting food for the next two days.” Hearing the threat, Sans swallowed hard, holding back bitter tears before redoubling his efforts, taking Papyrus’ cock all the way in with a mewl and swirling his summoned tongue along the underside of his brother’s dick.


He needed to eat. He was so hungry. Papyrus hadn’t fed him in so long, and neither had his ‘customers’. Sans suppressed the memory of being violated roughly for money and instead focused on the task at hand.


“...45 seconds.” He definitely heard Papyrus’s voice being strained, grunts and moans egging him on. His brother was so close, he just needed to...


Sans gave a particularly hard suck and he felt Papyrus’s hand tighten on his skull, the crack spreading as he climaxed into Sans’s warm mouth with a curse.


5 minutes! He’d done it! But then, why was Papyrus smirking...?


“Check the time, pup.” Sans’s eyelights darted over to the timer Papyrus held in his hands before he deflated, sagging back against the wall as tears pricked his eyesockets.


Five minutes and two seconds.


“Nyeh. Clean yourself up, you’re a mess, then cone to my room. I still want to play with that pretty little cunt of yours.” A hand slipped down the skirt Papyrus forced him to wear and rubbed pointedly at Sans’s pussy, one finger flicking his clit as the smaller monster shuddered, yet felt nothing.


He had lost.


Sans dragged himself to the bathroom after Papyrus left, mind blank. Pathetic.


He stared out the open window at the snow below, three floors up.


It was a long fall.