鳥籠の姫～絶対妊娠の姉妹悦辱～（Torikago no Hime ~Zettai Ninshin no Shimai Etsujoku~）

Rule everything - get everything

I, Kagokura Masaki (name can be changed), was called by my great-aunt, the head of the family, and returned to my hometown village. I arrived with my younger sister Karin and older sister Satsuki, and was greeted by my cousins Yuzuha and Kaede. Following their words, I headed to the main family mansion, and someone appeared before my eyes. It was -

And then, as I was rekindling my friendship after a long time, a letter was handed to me. "Get your hands on the family's great treasure." "Big brother?" It was a beautiful woman with white skin and blue eyes, Keikoku. "You said you'd come... I've been waiting for you for a long, long time...Big brother."

A sense of déjà vu emerged from the depths of the turbulent waves of memories. Even though it was the first time we'd met, I was seized by the feeling that we'd met somewhere before. "Big brother... I love you." The words of the conqueror make my mind and body waver, separating me from reason and thought, and laying bare my desire.

I want to violate her. I want to dominate her. Everything about her... her body, her mind...! My mind and body, gripped by desire, shake off the feeble resistance of reason and thought that try to hold me back, and pounce on the conqueror. And then I learn why I was called to my hometown, Torinose Village, which is suffering from depopulation.

I have been tasked with the mission to impregnate Karin, Satsuki, and the others and have them give birth to the next generation in order to save the village and the clan from the threat of extinction.

--Control everything--Get everything. The feelings hidden at the bottom of the well of memory, and the intricately intertwined customs and destinies. When they intersect, the first step begins on a path that leads from the past to the future.

[Translated from the official site]