MTL - Law of the Devil - ~ [The physical book of this book is listed! 】

An 18-year-old poor college student tried to apply for a job as a tutor but his life almost ended as demons' meal. In his last breath, a mysterious woman gave him a strange power. When he opened his eyes he had turned into a demon with a system that would turn him into… A pervert.

Now he must lived with his dual identity as a model student named Ethan and an incubus named Damian.

Luis Hartmann activated the mysterious Portal and began the journey of traveling between two worlds. In Immortal world, there are various immortal cultivators who can destroy mountains and live for thousands of years. In his own world, it is a Western fantasy realm where people can become knights or wizards, with different kinds of races. Luis, using the resources of both worlds, rises through the ranks. The life seed that knights awaken when becoming apprentice knights transforms into spiritual roots in the immortal world. With strategic wisdom, he helped his family become the eternal family, dominating both worlds. [Knight + Martial Arts + Immortal Cultivators + Family building]

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?

Back in 1991, in the face of this golden age, Chen Jianghai swears that he will only live in three words in this life: Lin Wanqiu! The story of a reborn person who built an electrical empire and reached the pinnacle of his life!

- Description from novelbuddy