Cold Husband, Don't Seduce Me - Chapter 43

Our protagonist Caam is a man from Earth that was reincarnated into this world as a demon. In order to survive, he spared no effort in avoiding the sparks of battle and without noticing it, he became strong himself.

Follow Chen Ming as he accepts disciples, establishes a sect, and fights his way in a world that deems him a cannon fodder.
He goes against any common sense using his wits and novel knowhow to finish missions and arm himself against his cruel fate.

- Description from Novelupdates

(Non-system, multiple female MCs, both good and evil)Fang Ling, who possesses the Chaos Sacred Body, was fiercely fought over by various forces since his birth. His heart, right eye, and treasured bone were successively taken away...After many twists and turns, the critically ill Fang Ling was placed in front of an ancient temple by a kind-hearted person. No one knew that within this ancient temple, five unparalleled masters were in seclusion. They had been hiding there for tens of thousands of years, suppressing the Immortal Heart of the Demon Ancestor.When the Immortal Heart erupted, the five masters were unable to contain it and took a desperate risk by implanting it into the infant's body. The fusion of the incomplete Sacred Body and the Immortal Heart led to the birth of a peerless monster...

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?