Death March kara Hajimaru Isekai Kyusoukyoku (WN) - Side Story: Sisters

A 30-year-old NEET is reincarnated into the body of an otaku that choked to death on instant noodles. As he comes to grips with his new life, he realizes that this world is subtly different from Earth. The denizens of this world are far better looking, and this new world also possesses futuristic technology as well as mysterious Yin Yang masters!

After reincarnating, he realized that he was endowed with a miraculous game-like system, which enables him to increase his own stats and transcend the limits of the human body. This system even has a game-breaking ability to save and load in real life!

In this new world that’s akin to a 2-D game, he just wants to enjoy life and head for a glorious future… However, he is quickly embroiled in a complex plot. Can he unlock his true potential and utilize his system to break the shackles that confine him and discover the truth about his previous body’s circumstances?

- Description from novelupdates

Jian rue gazed back at the ugly gray alien while stumbling and running. he clumsily tossed a stone at it “Fuck just leave me alone!!!”Suddenly a warm pair of hand grabbed his waist and tossed him over a study shoulder.“Xing yu!! let me down! you fucker!!!”The said man chuckled and playfully smacked his butt. “Honey, I'm saving your life~”“I had it under control. Now, let me go!” Jian rue bit his shoulders hard until the sweet taste of blood filled his mouth.“Hiss.. baby, you're making me hard~”Jian rue froze. “W-why are you following me! why me..”Xing yu stopped running, and with a swing of his sword, the ugly tentacle alien was slayed. He gentnly pulled him down and hugged him close. Peering into his eyes, he smirked, “Because you are my betrothed,”

Where there is light there shall be darkness

Hero? Nahh I'm the demon.

In a world where the demons are looked on as the incarnation of evil, the human-demon war raged on across the whole continent.

The Seraphims, protector of humanity, and the Demon lords who rule across all demonkind. Amidst all the chaos, Simon was reincarnated as the lowest ranking demon noble.

A brutal world where the strong feeds on the weak, eat or be eaten, kill or be killed. A demon far off from humanity….a dream unfulfilled in his previous life will be achieved in this life. Taking on the moniker of Laplace, he destroys all his enemies and rise over them.

[Ding! The host is about to die socially, the Goddess Conquering System is activated! ][Binding successful! ][Rebirth begins! ]----What Happened wasn't i caught masturbating, how could i rebirth?“System, Introduce Yourself”----[Goddess Conquering System Activated!][Main Strategy Mission Unlocked!][Target – Clara Mackerel][If Clara violently resists or if you experience social death after being intimate with her, it will be deemed a failure, and you will restart.][Upon completing the mission, system rewards will be given]----“System, do you have any other functions? Is there a beginner's gift package?” Harry asked expectantly.[This system only issues Goddess Conquering missions and rewards for completing those missions.][In the event of failure, the system will select a time period for the host to rebirth.][Other functions must be discovered by the host.]