MTL - Midnight Offering: Hades’s Little Pet - Chapter 219 Twenty years ago

[Nakseong High School, the heads of 300 people exploded!] Lee Joon, an ordinary high school student.During the entrance ceremony, he was caught up in a strange phenomenon and died.[You have died.] [Restarting from checkpoint.] [Loading…] And then a message appeared before his eyes.『Welcome to Nakseong High School that is full of mysteries and secrets.Uncover the dark secrets hidden around the school, or fight against urban legends and myths to earn points and unlock special abilities.Then, gather companions and stop the resurrection of the demon king before you graduate.The world is in your hands.』

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

- Description from Novelupdates

In a world where ancient magic has been resurrected. Atlas, an orphan from Earth, finds himself transmigrated into the body of a child and possesses the rare Void Magic. Harboring such power, he’ll walk the path of becoming stronger and stand free in the sky above all existence!The tale of the Legendary Void Walker is about to begin!The cover doesn't belong to me! The title was done by TiramisuAndCoffee!