The Alliance Marriage Went Wrong - Chapter 12 - What A Strange Family

Xia Yan passed through to the world of Bleach and became an eleven-year-old boy. He was rescued by Renji and Rukia in the Seireitei, and he was studying at Shin’ō Academy, and he was a student of the same class.
He is a top student of the Shin’ō Academy, and he is vying for strength by various teams. In the end, he has entered the first team of secret mobile maneuvers.
He will use punishment to kill every person who tries to threaten the martyrdom and protect his loved one.

- Description from Novelupdates

This is a story of a modern man returning to ancient times, returning to a real world without any extraordinaryness, and slowly rising by relying on the ability to attribute all data.

- Description from novelbuddy

Evolution, it is the process with which the most fit for survival pass down their winning traits. What if this could be done on one animal, one object, one person, what traits would evolve.

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Humanity has been entered into the grand inter-realm competition for sovereignty of all realms.

Darwin has been granted the gift of evolution