Isekai Maou to Shoukan Shoujo Dorei Majutsu - Volume 10 Chapter 1 part3-4

“If I don’t die… I swear I will act on all my evil thoughts..”

Not exactly everyone’s typical thought when they’re about to die. What will a cowardly young man do when reincarnated with the evil powers to redefine his destiny? Can the natural kindness of human nature triumph over evil? Will he become the cold-blooded demon king of legend, or will he forge his own path and rain down another kind of terror?

Ajax was an orphan who survives a massacre along with his friends but unfortunately gets separated from them.

Fortunately, after a turn of events, he successfully gains a system which helps him increase his cultivation, but doesn't know what it is called.

But he knows one thing for sure, this system is very powerful and helpful in taking his revenge.

“Whoever you are, I am gonna find you”, Ajax mumbled himself with a disgruntled expression.

In a world where Summoning of an elemental spirit is done through a dream when they are 15 years old, Ajax with the help of a system and his summoned spirits sets out on a journey to seek revenge against the mastermind behind the massacre.

Su Shuilian was the first legitimate daughter of a renowned embroidery family, but she was murdered by her jealous family member. After death, Su Shuilian’s soul enters an unknown female body who lives in a dynasty she had never heard of.

While trapped in the wilderness with her wolf pup companions, Shuilian picks up an assassin who was betrayed by his organization and saves him from the brink of death.

After making it out of the dangerous forest, the two travel to a small town with few inhabitants. There, they find a location with a picturesque scenery and disguise themselves as a married couple to buy a house to settle down in.

She was a girl unfamiliar to this world, and he was an infamous assassin. Journey with them as they adapt to their new life…

- Description from Novelupdates

Perhaps it is the choice of fate. As a senior otaku, Qian Lingfeng got the “steel shell system”. However, when he swept the world with the system, became a local rich man, made all kinds of beautiful women, opened a harem, and realized the ultimate fantasy of thousands of otaku, he found that things seemed far from simple!
When the end comes, biochemical zombies suddenly come down, fierce beasts are in power, bloodthirsty zerg roam to kill the world, and human lives are comparable to dirt. Where will weak human beings go in this world? Is humanity going to be extinct? Or … can an otaku save the fate of the human race?

- Description from Novelupdates