MTL - The Last Slag - Chapter 1 Zero residue

The whole world is subjected to a highly dangerous standardised exam called the Global Examination. Answering questions by putting their lives at stake, they would live if they passed the test. Every month the exam will undergo reformation while, occasionally, it is random.

When she reborn, she finally understood; men can never be relied on.
That being the case, she can only rely on herself to win, that
splendid brilliance she yearned for, in this lifetime.

To my scheming Stepmother and ruthless sister, I will
destroy all your backings, pull off your wings, and step on your
arrogance! As for Grandmother whom speaks kindly but has a snake-like heart,
and a father who is hypocritical and exploits advantages; I will tear
off your pretense and cut off your hope! Let’s see how you can still
scheme against me!

Witness her splendid fight against her stepmother, punish scum men,
and create havoc in the imperial court, as she soars with the wind and
rises above the water!

But as for that man who still stands! How dare he play with my heart?

- Description from Novelupdates

For unknown reasons, he finds himself transported to a parallel world's Japan, unexpectedly taking over the body of a soon-to-be high school student who had died accidentally. Surprisingly, he did not inherit any memories. However, the first challenge he faces upon arriving here is a language barrier...Just as he struggles to communicate with his new family, a heavenly voice arrives: the black technology system has been activated, and the initial item—translation konjac—has been distributed.This is the story of someone with above-average intelligence but almost no physical strength in the Classroom of the Supreme Power.

After being betrayed by her fiancé and her cousin sister, she accidentally rescued an elegant but indifferent young master. Never did she expect to marry him and surprised many!