Starting With Contract Pets - Chapter 13 - Explosive Potential

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 being rescued from the perpetual life of slavery as an Arcane Vessel, Theo is given a choice: To continue with his sad and miserable life, or to join a group of Mercenaries called The Ak’ashi Guild and change his life forever.Upon choosing the latter, he must now go through immense challenges and learn even more truths about the world than he ever thought existed.... All while doing his best to survive in the current age—the Arcane Era.Tags: Fantasy. Action. Adventure. Magic. WeaktoStrong. Romance. NoHarem. SliceofLife.

Takamine Haruto transmigrated into a crossover anime world. His childhood friend is Eriri, his deskmate is Yukinoshita, the school beauty next door is Kaguya, and his new neighbor is Gabriel.He originally thought he could enjoy a peaceful life in this slice-of-life anime setting!But then—he stepped outside and found the Female Titan, Annie.Around the corner, he ran into the gluttonous Kamishiro Rize.A concrete statue that twists people's necks the moment they look away?A shy entity that hunts you to the ends of the earth if you make eye contact?An immortal lizard that adapts to any environment and continuously evolves?Takamine Haruto was overwhelmed.To maintain his peaceful daily life, he established the SCP Foundation to contain anomalies from across the multiverse!