The Daily Life of the Demon King - Chapter 1: ": Meeting with the Old Man"(Revised Version)

After an unexpected death, a soul finds itself reincarnated into the body of Itsuka Shido, an ordinary teenager in a world filled with powerful spirits, magic, and dangers from other dimensions. With the help of a mysterious system integrated into his body, Shido gains the ability to travel across worlds, summon legendary anime characters, and unlock a wide array of random skills and abilities.Disclaimer: The cover isn't mine, credits to the original artist.

16 years old-- most boys would be falling in love, as their hormones all rise to unprecedented levels. Most boys at Riley's age would have dreams; dreams that will slowly grow into passion. Riley, however, at age 16... killed the world's number 1 superhero.

“I'm going out to do something, so I can't take care of you any more. You can go down the mountain and have fun. But if you can't find someone who matches your Innate Pure Yang Body in three years, you're finished!”These were the last words the old man, who was Lionel Yeager's teacher, threw to him before he vanished. Meanwhile, having mastered most of his master's skills, Lionel Yeager went down the mountain and took his first step into civilization for the first time in years.With his unparalleled medical and martial arts, he sets forth on a journey, befriending new allies and crushing all the enemies that stand in his way, as he attempts to resolve his Pure Innate Yang Body constitution, and cultivate to the top of the world!

One day, Luo Jian woke up from his sleep and found himself in a locked chamber where the door and window were all sealed. A note with a few lines written on it was tacked to the wall: “Escape from this room within an hour, otherwise, you will die.”

There is a sequel called Reincarnation Night (轮回之夜) that takes place in the same universe but has different main characters

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