History's Strongest Son-In-Law Living With The In-Laws - Chapter 140

A series of short stories in the world of Toaru Majutsu no Index organized into chapters featuring Kanzaki Kaori as the protagonist, going around the world and space doing missions for the Church of Necessary Evil, however, there is more than meets the eye as each incident is connected.

One chapter was bundled with each limited edition release of the Toaru Kagaku no Railgun anime DVD and BDs, with all of them together being equivalent to a single normal Toaru Majutsu no Index volume

During the Yongle period of the Ming Dynasty.

Zhang Anshi was ignorant, and he committed a heinous crime.

His brother-in-law is the prince? Oh, that’s all right!

- Description from novelbuddy

Crimson Vale Academy—where reputation is currency, and failure is a stain you wear on your sleeve.Behind gothic walls and spotless uniforms, students aren't just educated—they're measured, ranked, and pitted against each other in a brutal meritocracy. Privileges are earned, not given. The strong rise. The weak vanish.Enter Kairon Vale, a transfer student marked Rank D—the bottom of the bottom. No badge. Just a stitched black fang, branding him as “Obsidian”—a warning to others.In a system where points dictate your value, Obsidian-ranked students claw for every opportunity to ascend into the prestigious Golden or Platinum ranks—where comfort, power, and influence await. But for most, it’s a losing battle.Yet Kairon isn’t here to fit in, impress, or play by their rules. Cold, calculating, and impossible to read, he watches the system… and waits. Because while the academy judges worth by numbers and names—he understands something deeper:Everyone wears a mask. And every mask can be cracked.Let the games begin.