Ze Tian Ji - Chapter 1130 – The Twenty-Ninth Night

Kyo Mazuru traveled to the world of Bleach and landed in the forest of Menos Grande at the beginning.Picking up a asauchi left over from Shinigami's death, and starting with a sword, he spent hundred years in the forest of Menos Grande to survive, slashing countless hollows, and his slashing skills reached the peak, until one day, he met a man who claimed to be Mr. Aizen Sōsuke!Mr. Aizen couldn't bear him to live alone in Hueco Mundo, so he invited him out of there and brought him to Soul Society!After that, Kyo Mazuru's Shinigami career began!

A side story series featuring the girls of Kyoukai Senjou no Horizon.

The aliens came with hostility.
Facing the invasion of aliens, human beings are weak like ants.
So this is the end, the real end.
But there is resistance when there is an invasion.
For some, this is not the end, it is war.
So this is war.
Real war!

- Description from Qidian