Secret Wardrobe Of The Duchess - Chapter 21

A mortal youth accidentally stumbled upon the path of immortality and struggled to move forward on the arduous journey of seeking immortality.The road to immortality is more difficult than reaching the heavens, yet despite the countless obstacles, his determination to pursue immortality remained unwavering.Looking back, the green mountains still stood, but his old companions had all turned to bones.

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

Xiao Lou was killed in an accident and reborn in the Card World.

I just left an honest review, and I was reincarnated. But not into the novel I criticized—into the world of [SSS-Class National Power Heir] .I reincarnated as Baek Seo-jun, the older brother of the original protagonist, faced discrimination, and was discarded as a sacrifice.And then I experienced hell.With the power of the final boss, I will exact revenge on everyone—whether it’s the original protagonist or the villains.[The protagonist who has gained the power of the final boss]