My Sweet Dr. Xu - Chapter 4: The Woman He Loves

I was a genius in the Earthen Plane.

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

[Are you crippled?][Did your fiancé break the engagement?][Did you lose your family to a demon attack? Are you the last surviving member of your clan, seeking revenge?][Does your family look at you with pity because you're the only one without any innate spiritual roots?][Are you tired of being told that you're a 'waste of resources'?][Are you stuck with no way to progress? Are you tired of being weak and helpless?][Well, have no fear! This Supreme Master is here to help you!]

Read at least six chapters, then prepare to crave the rest.The main character will show up in Chapter Five, though I don't recommend skipping the first four chapters.-----The world was celebrating. The Demon King was dead, along with his Darkness Generals.Humans led the other races to war for subjugation. They killed all, and none were spared. However, thousands of years before this happened, a piece of history was altered by time itself. In fact, the Demon King didn't have four generals but only one, which he sealed and sent into eternal slumber. Just as he started to close his eyes, the chains locked away for eternity shattered into pieces.