Shiki clipped the belt around his waist and stashed his stolen kitchen blade into his pants. He didn't have a holster for it, but the way he put it in, he was confident he wouldn't accidentally stab himself. He was thankful he was given his own room so he could do this in peace, avoiding his brother while preparing to leave. Not that he'd have to worry about Rin for much longer now, if things went according to plan, which Shiki was more than happy about. The boy was far too clingy for his liking.

He stared at himself and his expression in the mirror, his stoic face scrunching up as he glanced down at the almost visible knife. He wished he could get something better, but with Rin always around, it was the best he could do.

With only the moonlight coming through the window and their foster "parents" out doing god knows what, Shiki stalked out of his bedroom and walked silently down the hall. He'd practiced making his footsteps as quiet as possible, but even with all that effort, he hadn't even made it to the entryway before he heard a door opened. He groaned inwardly as he heard frantic footsteps behind him and turned to see Rin running up to him, dressed only in a white shirt and pair of boxers, his usual sleep attire.

"Shiki!" the boy called as he had to quickly stop his forward momentum, almost crashing into Shiki. Once he'd stopped, he caught his breath. "What are you doing?"

"How did you hear me?" Shiki asked.

"I just did. I'm really good at hearing you," Rin said with a satisfied smile that made Shiki's temper flare.

"I suppose it doesn't matter. I'm leaving," Shiki said as he turned to leave, only to feel Rin grab his arm.

"Where are you going?" Rin asked.

"None of your concern," he replied and tried to get his arm away, but he'd come to find that Rin had a surprisingly strong grip.

"You shouldn't leave while mom and dad are out."

"Those aren't my parents. Release me, now," Shiki said, adding a bit of edge to his voice to get the point across, but Rin just stubbornly shook his head.

"I was wondering why you took the knife and were even more distant than usual lately. You're leaving leaving, aren't you? Like you don't want to come back?"

"Release me," Shiki repeated.

"Look, I'm not afraid of you dying or something like that. I know you're pretty strong and everything," Rin went on. "But I can't let you leave!"

"And why is that?"

"Because I'll miss you," Rin replied quietly, and Shiki rolled his eyes as he groaned.

"You're pathetic," he said. "Now let go." He took a step towards the door only to have Rin pull him back.

"No! I won't let you leave!" Rin shrieked so loudly that Shiki's ears hurt.

"Get off me," the boy snarled.

"No!"

"Get off!"

"NO!"

"God damn it, I said GET OFF!"

With that, Shiki grabbed Rin's arm in return and used all his strength to fling him across the room and into the wall. A portrait fell as he collapsed to the floor with a cry of pain. Shiki had turned back towards the door, but hearing that cry made him pause as a surprisingly strong shudder ran through him. He took a few moments before slowly looking over at Rin, who was pulling himself off the floor and clutching his arm, which seemed to have a small cut through both his clothes and his skin. At the sight of leaking blood, Shiki felt another shudder. Although he knew what the feeling was, it surprised him. Something about how pathetic and weak Rin was made him feel…good.

He smirked.

"You'll miss me, huh?" he asked as he turned his body towards Rin, and finally met his eyes.

"Y-Yes," he said, confused as to what Shiki was doing and fighting the tears in his eyes. Shiki began to walk towards him, feeling the cold metal of the knife against his skin as he removed it from his pants and tossed it onto the couch.

"Why? Because you know you're too weak to survive on your own? Because you're too pathetic to stand up for yourself?" Shiki asked as he stopped in front of the boy.

"No, that's-" Rin started as he tried to keep up, only to have his world turn black, then white as Shiki kneed him directly in the face, causing him to fall back onto the ground as he cried out in pain. He fell back onto the broken glass of the portrait, which ripped the back of his shirt somewhat. He looked up to see Shiki looking down at him with a sinister smile.

"That's it, isn't it? You need me around because you'd be too afraid to do anything without me to protect you," he said as he brought his foot down on Rin's chest, knocking the wind out of him. Watching the boy's face contort in pain sent another shudder through Shiki that made something in his tighten. "That would be cute, if it wasn't so disgusting."

"Sh-Shiki…what are you…?" Rin asked between coughs.

"Honestly, I'm not sure. I should've just left by now, but…I've never quite felt like this before," he said as he ground his boot further into Rin's chest. "So I felt the need to…explore it, whatever it is. It doesn't matter since I'm going to be leaving anyway."

"I don't…know that you're talking about," Rin said, and Shiki nodded slightly before bringing his foot back up and slamming it down directly between Rin's legs. The scream that came out was far louder this time, and as Shiki listened to it, he felt himself becoming fully hard now, especially as he could feel the outline of Rin's own member through the boot.

He wanted more.

Stepping back as Rin cupped his groin, curling into a ball to do so, Shiki removed his boot, kicking it aside as he knelt and grabbed Rin's hands, pulling them away so he could push his sock-covered foot against Rin's penis, crushing it under him. Rin gasped as tears started to stream down his face, and Shiki almost felt a moan escape him as he moved his foot around, pushing harder into his groin, even managing to push against his testicles as well.

"You disgust me," Shiki said, and Rin merely gasped. "Though I must admit…this is quite fun." He smirked as Rin looked up at him, then went wide-eyed. Shiki knew why—the pants he was wearing did nothing to hide his arousal, and Rin's face became one of horror and confusion, but also mixed with something else Shiki couldn't identify.

But that's not what he was focused on. He wanted more.

Before either boy really knew what they were doing, Shiki grabbed him and flipped him onto his belly. When Rin tried to get up, Shiki slammed his foot onto his back, both crushing him underneath him and making him groan in pain. Shiki licked his lips, letting his body simply do what it wanted, and let his arousal guide him as he reached down and grabbed Rin's boxers. Rin gasped and once again tried to get up, but could only squirm as Shiki slowly pulled the boxers down over the boy's behind. Something in his chest tightened as he took in the sight of his brother's petite little butt, soft and smooth. Rin was shrieking for help at this point, his cheeks red with shame, a shame that only fueled Shiki further as he grabbed the boxers into a handful and yanked.

They tore without issue, leaving only a scrap trapped underneath Rin's body as Shiki threw the rest aside, feeling a tremor run through him as he looked down at the pale butt. Rin continued to struggle but seemed to be nearly powerless against Shiki. All that stopped however when Shiki reached down and harshly grabbed at the boy's ass.

"Wh-What are you…?!" Rin cried before Shiki reached his hand back and struck his behind as hard as he could. It was so hard that Rin felt his breath escape him before he let out a trembling cry of pain. He barely had a moment to register what had happened before Shiki struck him again in the same spot, and then again and again.

"You're disgusting," Shiki said even as it almost seemed like his actions said otherwise. Rin was trying to plead with him to stop, only to be hit again. He managed to get himself a little off the floor, groaning with pain as his cheeks stung, before Shiki wrapped an arm around his middle and yanked him up, slamming his pelvis against Rin's butt as the scrap of fabric fell to the floor. Rin wasn't able to get a word out as he felt Shiki's erection poking his butt through his pants before Shiki grabbed his cock, squeezing it as Rin's entire body trembled with fear and arousal. He couldn't understand what was going on, and why Shiki was touching him, hurting him like this.

"You're bigger than I would've expected for someone so worthless," Shiki whispered in his ear as he quickly used his free hand to thrust open his pants. Rin froze as he now felt it, Shiki's raw cock resting between his ass cheeks as Shiki began to move his hips up and down. Rin let out a moan that left his red face burning even hotter as he reached for the hand clasping his cock. Shiki only squeezed harder, however, and Rin was terrified to feel himself growing hard. He could almost hear Shiki's smile.

"Like I said, disgusting. Getting hard to this," he said.

"B-But…you're…!" Rin started, only for Shiki to yank on his cock, cutting him as he groaned. Shiki's thrusts continued as he grabbed one of Rin's cheeks and pulled it aside, feeling another tremor as he could see it now.

His goal.

On any other day, in any other instance, he would've felt disgusted with himself. Perhaps even now he still did, but he also was letting his cock do all the talking. He let it guide him, to punish this boy for simply being a constant annoyance and trying to stop him when he finally found something he wanted to do. He wanted to teach him a lesson.

It was why he had no hesitation when he plunged his head into the boy's hole.

The boy softened and then immediately hardened again as Rin let out a scream of pain. That scream shot to Shiki's very soul, and he began to laugh as his dick pulsed, pushing him to go farther. He pushed forward, burying himself deeper as Rin's shrieks continued. Rin tried to turn and attack, but Shiki let go of his ass and instead grabbed his neck from behind, pushing it down and pinning him with his small ass in the air. He grunted and groaned as Shiki kept his other hand on his cock, stroking it almost gently while he began to thrust in and out of his tight ass. The wall he clenched around Shiki brought him an intense satisfaction he hadn't even known was possible. It was almost painfully good as he slid back and forth, barely able to even focus on stroking Rin at the same time.

Rin felt like he was melting. He felt intense pain through his ass, but at the same time, Shiki's slender fingers felt incredible on his already aroused cock. It was a strange dichotomy that clashed inside him, making him unsure what to think or even how to feel. All he knew was that whatever was going on in his mind, his body was clearly enjoying it in some way given that he was aroused.

So Shiki kept going. He kept pounding into his ass, feeling disappointed when Rin's body seemed to adjust and it became a little less tight. Even so, he could feel himself already getting close, getting off on both how it felt and Rin's clear pain. He stroked Rin off faster and faster, moving his hand up and down as quickly as he could, feeling his dick pulsing every few seconds, indicating that he too was approaching his own climax, despite his pain.

"Gahhhh…haaaaah…" Rin groaned, and now Shiki moved his hand from the boy's throat to hook his mouth and pull his head back so fast that he groaned. He continued pulling hard, forcing Rin to taste his fingers as he began to slow down, still thrusting hard, just at a slower pace. He could feel it surging inside him, and so he plunged himself as deep as he could to erupt inside his brother's ass, while maintaining his stroking as much as he could. Some part of him wanted to get Rin to finish too even if it wasn't really necessary. Maybe it was to rub in his powerlessness further, he wasn't sure. Either way, even as he was unloading so much into Rin that it was leaking out onto the floor, he kept going until Rin too experienced his own climax. When it happened, Rin reared back and, although it sounded off since Shiki was still hooking him, he moaned as he came as well. He leaked at first before eventually coming hard onto Shiki's hand, where he felt it flowing down over his hand, covering his fingers in the sticky white substance. He waited for Rin to finish before removing his hand and flicking whatever he could onto the floor.

Once Shiki pulled out, Rin, now freed, collapsed onto the floor, panting, his face somehow both red and pale at the same time. Shiki stared down at the boy as he felt his lips curling into a small smirk.

Maybe he wasn't as bad as he thought.

"What…the hell?!"

Shiki and Rin turned to see their foster parents standing in front of the now open front door. In their deep arousal, neither of them had noticed the door opening, and now their parents stared at them in a mixture of horror and shock. Shiki blinked as he felt only a brief moment of panic before he moved.

He grabbed the knife and lunged.

Rin turned his head away but he still heard the horrific sounds as well as felt some blood fleck across his bare skin as he slowly got to his feet. It only took a few seconds before the sounds stopped, leaving the only thing breaking the silence being a steady drip onto the floor, which Rin was sure he knew the origin of.

A few more seconds passed and Rin felt Shiki's hand on his shoulder. He looked back at Shiki and winced as he saw a splatter of blood on his face, while the rest of him had much more than that.

"Grab whatever is essential," he said coldly. "You have five minutes before I leave you behind."

Rin didn't ask questions, and simply followed directions. He ran upstairs to his room and grabbed some clothes as well as sentimental things he wanted to keep. He packed them up in a suitcase as quickly as he could and made it back downstairs just as Shiki was turning towards the door. It was then that he realized.

"I-I forgot to put on something…" he said, still only wearing his shirt, one that barely covered his junk. "Give me one second-"

"No, we leave now."

"But-"

"Now," Shiki said before he started walking, and Rin had little choice but to follow.

Little did he know that he would soon become his brother's little slave, only there to satisfy him when he was bored or stressed. It was a relationship he eventually grew to tolerate, and even eventually love.

Even if Shiki never really felt the same towards him.

At least not in any way he'd ever admit.