Mistress Of The Evil Forest - Case 177: Operation Plazma: Red snow.

A 13-year-old deaf teenager living in the 21st century suddenly found himself as a young boy in Japan during the early 1900s. With two World Wars, two nuclear bombs, Hitler and many other disasters awaiting his future, he thought things couldn't get worse.Except it did.He found out later on that he had actually reincarnated into the world of Demon Slayer where man-eating demons ruled the night. He thought things couldn't get worse.Except it did.But hey! At least he had unparalleled talent, incredibly special eyes and future knowledge.How will the story of Demon Slayer change with the addition of this unique character? Will so many still die if the Hashiras had one more pillar in the final battle?Or will the story end on a much happier note?

Feng slowly backed up to the door, “W—what’s up with you both?” Two tall blond men stalked closer and caged her in the corner, “Aiden, Ethan, you both are too—too close,”

From a media tycoon’s daughter to a poor plumber’s girl, but it seems that Yu Yao is unfazed? She opened the eyes of the sky, and her life has been opened all the way. She is an eighteen-year-old girl, but as soon as she turns around, she becomes a big boss who no one in the entertainment industry dares to offend.

- Description from Novelupdates

After putting a suggestion to add a mercenary in a bad Murim novel he read, Leo would finish a mission with his NPCs before sleeping. Or so he planned. For some reason, he was transported into the said novel as the extra mercenary added by the author. His loyal NPCs, a yandere secretary, a happy-go-lucky assassin, a sexy puppeteer, and two weapon maniac guys start to become sentient. He lead his mercenary band ’Hallowed Insects’ toward an an unprecedented future in a Murim most turbulent era while enjoying his time. Fortunately, they still have their futuristic equipment with them. Tang Clan have a Poison Dagger, they have a Photon Sword. Shaolin Sect has a Qi Blast, they have a Railgun. And of course... “How much are you willing to pay to employ us? By the way, Demon Sect pay us 50,000 Golds to join their side in the upcoming war.” ... he always sided with the highest bidder.