Shiniyuku Kimi, Yakata ni Mebuku Zouo

It happened without any warning. In a world that was peaceful superior beings suddenly appeared. They one-sidedly massacred humans and the world was swallowed by a whirlpool of chaos. While our heroine Mia was shopping with her family, she also fell victim. With her father, mother, and older sister dead, she desperately tried to escape, but before she could a different superior man appeared before her. Falling into desperation and prepared to die Mia took up a knife and stabbed the man. The next second, she lost consciousness. Not knowing what had happened to her, she felt a great pain on her stomach. "You hurt my body, now I can't allow you to die easily. Your sin... deserves ten thousand deaths..." And so when she recovered her consciousness, Mia was on a bed in a mansion. She didn't have a single wound on her body, and she was wearing a dress that didn't belong to her. In that mansion she re-encountered that superior man. He ordered Mia to live in the villa, where he repeatedly did inhumane acts towards her. Being crushed, stabbed, shot, spilling blood, being decapitated, being eaten, being dismantled... And every time she woke up she was on a bed in that mansion. Without a single wound on her body, and wearing a dress that didn't belong to her. At that mansion--- [Translated from official website]