Saga of Atlantis - Chapter 156 : Spirit Core

After seeking pleasure in the nightclub and a night of romance, he discovered there’s a seed in his stomach;

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 story tells the life of two people, a noble only in name and an older wife from the army, married through a tentative agreement. In the bone-chilling cold, they spend their time hunting, gutting, and cooking by the fireplace. Their daily life passes peacefully. This is the warm love story recounting their daily lives.

I got transmigrated into a game I’ve never seen before.

I thought it was a top-notch RPG and spent 30 years on it.

I retired as a war hero and planned to spend my remaining time leisurely.

But it turns out, it was an academy story?