Vengeance: Ex-Husband CEO, Please Love Me - Chapter 13

After breaking up with his girlfriend, he accidentally acquired a genius system and rose from there against the heavens, becoming invincible..

- Description from Novelupdates

When The Cute Kunoichis Spied on Their Teacher's Secret is a light novel written by Kazuma Kamachi and illustrated by Ryuushi Tajima.

The story takes place in a world where Japan never ended their isolationist phase, and agents from foreign powers are always threatening to steal the country's advanced technology. In order to combat this threat there has been a resurgence of ninjas that use Strategic Martial Arts, techniques that combine cutting-edge modern technology with a traditional foundation of martial arts and ninjutsu. The story follows Souha Sugiyado, a 17-year old ninja instructor and former ninja prodigy who was forced to retire from active duty by the wounds he suffered in his last mission. Souha's four students are all kunoichi who have all gained the rank of Elite Ninja, the highest official rank available to ninja. However, one day two Shogunate ninja approach him with the news that his four students have gone rogue and have stolen a portable modular nuclear reactor, and thus they ask for his help in bringing his students to justice.

Roan crossed over and became an FBI agent.

Several years later, when interviewing the world-renowned detective Roan Greenwood, the reporter asked:

“Excuse me, what made you persevere on the road of solving the case?”

Roan tilted his head and glanced at the sports car beside him, the villa behind him, and the beauties in the villa, and smiled slightly:

“Of course it’s the bonus after solving the case.”

“???”

- Description from novelbuddy

Tang Shaoyang, an orphan who dropped out of the middle school to fight on the street as he found out school was useless for a penniless orphan like him.

Tang Shaoyang dropped out of his school, fighting on the street, and made a name for himself. Berserker Tang from Youyouliucun.

Afterward, Dragon Wing triad recruited him and everything was good for him. Even though the public deemed him as a tumor of society, Tang Shaoyang was having a decent life. Until one day, everything changed as an absurd and strange game started.

[… Game starts! Stage one: Survival for The Fittest!]

After the game started, zombies appeared out of nowhere.