MTL - How to Deal with a Tsundere Gong - Chapter 4 Late call

A military enthusiast with dreams of serving, shaped by his father’s influence and a bookshelf full of war theories, finds himself unexpectedly reborn into a fantasy world he’d recently read about.Now an orphan, he faces impending destitution in a land governed by strict caste systems. But with the Reich Empire Academy Entrance Exam as his potential salvation, he’s armed not with magic, but with a vast knowledge of military tactics from his past life. As the date of his expulsion from the orphanage looms, he’s determined to leverage his unique skills to change his fate.

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

After losing his parents to an accident, Haruto is thrust into a state of depression. Realizing he never had the power to change things, he eventually took his own life. Before moving on, he’s selected by beings greater than his understanding to balance out a world suddenly facing peril. The world of Mordell, where demon-like creatures and beasts roam, and Guilds of ability users called Warlords are the force to combat these creatures. Armed with the power to change things, he has the choice. Continue living in despair or accept his second chance and become a true Warlord.

Reincarnated into his college days. Zhou Yuwen knew the importance of a persona. In this life, Zhou Yuwen’s labels were aloof, mature, and exceptionally talented! “I’m quite traditional, I believe that if you’re in a relationship, you need to be responsible, so one must be extremely cautious about dating.” “Zhou Yuwen, let’s get remarried!” “Damn it! Are you poisoned or something? I haven’t even been married before!” “Stop talking nonsense! We were married in our last life!” “That was in the past life!” “Remarry!” “Go away! I have a girlfriend!” He fled, she chased! He couldn’t escape, even if he had wings!