The night of the full moon. Inuyasha sat by himself in a cave with a fire, the others were off looking for the shikon jewel without him. He had Kagome's little mirror thing, it showed him he was human. He growled at it and put it down. He hated his human side. He was weak and unable to do anything useful.
Sitting with his back pressed against the cold cave wall, he began to doze.
Sesshomaru inhaled deeply. Human. Nearby. Not just any human, half human, half dog yokai. Inuyasha. His brother. He smiled, his brother was experiencing the effects of his mixed blood. He was a human tonight.
Following his brother's scent, he found him mostly asleep in a cave. His human senses so dulled, he didn't hear the older demon approaching.
At last, a chance to do as he always longed to. With a surprising gentleness, Sesshomaru undressed his younger brother and laid him upon the cold ground. He gazed upon his brother's body, tanned, lean, musculed. He removed his own clothing, placing it in a neat pile.
Standing above his brother, clad in nothing, his cock standing erect, he grinned a feral grin. He stepped forward and grabbed his younger brother by the hips, lifting him, his nails digging into the soft flesh. He let his younger brother fall, right on to his hard cock, penetrating him completely, a shocked garbled yell of pain and surprise emaniting from the younger's lips. Brown eyes locked with golden.
Sesshomaru grinned wider, slamming the now human into the cave wall, his back hitting the stone with a resounding smack, he gripped his brother's biceps, pinning them to the wall. His brother's expression was one of pain, surprise, and anger.
Sesshomaru withdrew about halfway, a sigh escaping Inuyasha's lips, but he rammed his cock back in. The younger groaned in pain as his older brother continued to ram his cock deep into his virgin ass. Sesshomaru poured all his anger and rage into each thrust, blood was running down his cock and his fingers, he didn't notice.
Weakly, the younger tried to push him away, but Sesshomaru pushed him harder into the wall, pulling almost all of the way out, leaving only his tip inside and slamming all the way back in. A yell of pain greeted his ears, so he did it again, and again, and again. Delighting in the pain he caused the younger half demon. He leaned forward, to the neck of his brother. Inuyasha tried to squirm away, but Sesshomaru dug his nails in deeper, bucking his hips, causing a jolt of pain, and he sunk his fangs into the tanned expanse of skin, he licked the blood, sweet. He moved away from his neck, picking up the younger's legs and twisting him around on his cock so that he was now facing the wall. Sesshomaru fucked him relentlessly, he came multiple times, his cum running out of his brother's ass, mixing with the blood. He fucked him harder, cumming one last time before he pulled out and redressed, the younger too tired and in pain to move.
Smirking, Sesshomaru left, his work was done.