Born to Be Rebellious [Quick Transmigration] - Chapter 54: The Merman

Sure, the world is ruined, but I’ll live my own way. Of course, luxuriously and gorgeously.

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

A generation’s War God, once overlooking the world with disdain, had fallen into disgrace because of a conspiracy, becoming a mere son-in-law. However, what nobody had expected was that it was all part of his grand scheme, and when the winds of change blew, he, the king, returned, with the power to overturn seas and move mountains, as a dragon ascended to the heavens!

The ordinary 18-year-old Edo, during a nighttime walk, finds himself in a fantasy world where he gains a mysterious power that could shape his destiny.