Naruto: Starting with the Ōtsutsuki Bloodline - Chapter 20: The Mysterious Observer

Regardless on how developed a society becomes, assassins and prostitutes will never cease to exist. There’s no need to think of the former as anything mysterious, and there’s no need to look down on the latter. They are simply doing their jobs.

When Tang En crossed over planes, he was forced into this murderous and hopeless profession.

“You have great talent for assassination.”

Tang En: “Huh, I have this kind of talent?”

“That’s right, your looks are exceedingly plain, this is very useful to assassins.”

“……” Tang En, “But I haven’t even managed to kill a chicken.”

“Irrelevant, assassins don’t need to kill chickens, only people.”

“……”

The story is about a plain college graduate crossing over worlds after dying in an awkward situation. Inheriting the game-like Assassin System and a badass butler from the transition, he now has to adapt to survive in this dangerous, new world. Set in a Western Fantasy Universe.

- Description from Novelupdates

By the time I reached thirty, I hadn't managed to provide any of the happiness I wanted for my wife.I also still couldn't become the support my parents relied on.At this turning point in my fate, my income suddenly began to increase randomly.(A daily life tale in a wealthy family setting, featuring a single female lead and no harem.)

The Supernatural era descended, the rules changed, mystery arrived, and the world altered. Countless ruins of civilization emerged, and an abundance of Heavenly Materials and Earthly Treasures lay at everyone’s fingertips. Radical faction, “This is the best of times, entering a new world, excavating relics, mass evolution!” Conservative, “This is the worst of times, with countless monsters outside, once you leave the Safe Zone, extinction awaits humanity!” … Meanwhile, at a remote ruin, Lu Yuan successfully discovered new treasures and sought after the mysterious wealth, desperately trying to contact his fellow Earthlings. “Found a communicator, can it get through?” “Hey, humans—I’m almost becoming a god, and you’re still hiding in the Safe Zone?”

The well-known and recognized throughout the Stern continent, strong and mighty, as well as the unique Wizard of magic cures, the most outstanding genius of the whole continent, Jason got into the flow of time, back in the uncivilized era during the first failed experiment, 3000 years ago. This was the period when the magic healers didn’t exist. How will Jason apply his knowledge in this backward era, wherever he reach the peak of glory?

- Description from Novelupdates