They fill her up

Kentaro came almost simultaneously with his father. While his father pulled his cock out and painted his sisters face with all the cum that had been building up for years, Kentaro released all of his load into his sister's pussy, sure that it would pop through the opening to fill her uterus. His father exploded, shooting heavy ropes of cum onto her face, painting her skin with his seed, but Kentaro felt the backflow of cum shoot free from his sister's pussy and splash against his scrotum. His sister moaned in pleasure, dropping her head do the floor to let her father's semen roll down her face and chin, dripping into her mouth.

Realizing that his heart was pounding, his breathing was heavy, and his body was covered in sweat, Kentaro 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 looked to his father, he saw that he too was coming back to himself, the three of them momentarily under the control of something else.

Kentaro 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?” his sister 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, the three 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.