Game of Thrones: Knight's Honor - Chapter 314: The Five-Colored Dragons

He said coolly: “One million a month, stay with me!” She raised her eyebrows and smiled: “Pay a 30% deposit first, no credit!” Show no mercy. When the contract expired, she turned around gracefully, and when he chased after her, she found that there was already a kid the size of a kid beside her…

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Amamiya Hiroto is unlucky. His life consisted of misfortune after misfortune, culminating in an unlucky death during an incident on a school boat trip, trying to save a girl he barely knew. After death, he met a god of reincarnation who requested that the hundred or so dead passengers—one of them being the girl he tried in vain to save—be reincarnated into another world.

What happens when a scientist from a futuristic world reincarnates in a World of Magic and Knights? An awesome MC is what happens! A scientist’s goal is to explore the secrets of the universe, and this is exactly what Leylin sets out to do when he is reincarnated. Dark, cold and calculating, he makes use of all his resources as he sets off on his adventures to meet his goal. Face? Who needs that… Hmmm… that guy seems too powerful for me to take on now… I better keep a low profile for now. You want me to help you? Sure… but what benefit can I get out of it? Nothing? Bye. Hmmm… that guy looks like he might cause me problems in the future. Should I let him off for now and let him grow into someone that can threaten me….. Nahhh. *kill*-

Alternative: Leylin is transported from an advanced technological era into a medieval world— except there’s magic. Equipped with “only” his quick wits and an A.I. chip fused to his soul, he sets out to become the most powerful magus the world has ever known. In a land divided into the Light and Dark Magi, the weak can either be cattle or disposable slaves. Only the strong can determine their lives, and only they have the luxury for virtue. Yet strength is only a tool for Leylin, like any other. His goal, in the end, is his own.

Uchiha Kai has been cautious since he came to this world. He vowed that he must be cautious and go to the end.

But one day he received a mission – to cover the wave wind team to blow up the Kamabashi Bridge, Uchiha Kai knew that he was going to be unlucky…

- Description from novelbuddy