He cums in his sister's ass

Deciding that he wanted nothing else but to explode into her, he rocked his head back and groaned as he let go of everything that had been building. He exploded, shooting heavy ropes of cum from his cock into her. She moaned with pleasure, taking ever bit of it and he smiled. It was done. She was his forever now, forever going to remember how he took her harder than any man she’d ever been with.

Realizing that his heart was pounding, his breathing was heavy, and his body was covered in sweat, he let himself collapse. As the pressure in his veins slipped away, he felt his cock become flaccid and he began to realize exactly what he’d just done.

Sitting up, he looked at his sister’s face saw the look on hers. She was as surprised by all the things that had just happened as he was. He blinked as his thoughts of domination and control slipped away and he felt himself again. As he did, he turned quickly to the trinket that had caused all of this and found it blank.

There were no symbols or calligraphy. It was just a small, cheap thing that was probably purchased at a gift shop at some tourist location. There was nothing special about it.

“Kentaro?” she asked, equally confused.

Neither had an explanation for what had come over them, but neither could deny that they had felt it. Quickly picking up their clothes, they dressed in silence and exited the room, separating quickly so that no one realized what they had just done together. However, in the back of his mind, he was glad that it had happened and as he slipped in the yard where others were busy cleaning, he cocked a smile, the feeling of confidence still hidden in the back of his mind.