Sir, How About A Marriage? - Chapter 291 - Turning the Tide

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

“The ocean took everything from him—his memories, his past, even his name. When Eddy opens his eyes, he's met with unfamiliar faces and a world that no longer feels like his own. Rescued by Mr. Dand, a kind stranger, Eddy finds refuge in his home. As he navigates this new life, he develops feelings for Artur, Mr. Dand's son. But the past never stays buried. As Eddy's memories begin to resurface, he must confront the truth about his identity and the life he left behind. Will he still want that life back, or will his heart remain with Artur?”

Stealing Heroine from Protagonist with SystemWARNING MATURE CONTENT!!!!!R-18

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