Reincarnated as a Son of the Sword Saint and the Sage - Chapter 405: New Wife

One day, Zhang Fan, a poor medical student, receives a medical system from the future. This turns him into a new shining star in the medical field. Along the way, he must face medical corruption, competition, and infighting from other doctors, and even find time for a love life as he strives for the top of the medical field!

- Description from Novelupdates

Haruto Hayase was a normal high school boy in his third year, living a quiet life until his younger sister, Haruka Hayase, joined the same school. Haruka’s beauty and charm made her the center of attention, quickly becoming the school’s prima donna. But when a notorious gang leader set his sights on her, he did everything in his power to protect her—only to fail tragically. Haruka was brutally assaulted and tortured, and Haruto himself suffered an agonizing death. However, in a twist of fate, Haruto is given a second chance, waking up a year before the events that shattered his life. Armed with the mysterious ‘Debauchery System Slave’, he vows to exact revenge on those responsible. This time, he will use his newfound powers of the system and charm to seduce the loved ones of his enemies. From their mothers, sisters, and lovers to their closest friends, Haruto will make them his. His enemies will suffer as he steals what they hold dearest, ensuring their downfall in the most devastating way possible.

Insane. Traitor. Terrorist.

This novel is also known as I Possessed a Demon Sovereign

Chen Luoyang felt that something was wrong with his transmigration. After transmigrating, he possessed the body of the highest expert in the world, the Master of the Demon Cult, addressed respectfully as the Demon Sovereign.

Generally, aren’t supreme experts the ones that leave behind a wisp of their soul behind and occupy a new body of some miserable low-level youngster then they go on a journey of revenge and make a comeback?!

Or perhaps it would be transmigrating into a miserable youngster’s body and obtaining a cheat slowly walking the road to becoming a God?

But why did his transmigration seem wrong?

Now my environment is full of big shots and I feel like I’m going to be exposed!

- Description from Novelupdates