MTL - It’s a Stepmother, Not a Sister [70s] - Chapter 24 evidence

Kyoukai Senjou no Horizon chronicles the story of a futuristic civilization returned to Earth after constant warfare hindered them from traveling beyond the post-Apocalyptic Earth. At this stage, a small archipelago called the Divine States were the only hospitable land on Earth. In order to regain the space-faring technology they had lost after many years of war, they decided to recreate history with a book called the Testament as a guide.

It is the year 1648 in the Testament Era. Toori Aoi, Chancellor and Student Council President of the only academy on the airborne city-ship Musashi, faces the ten-year anniversary of the death of his childhood friend Horizon Ariadust in an accident. As he prepares to celebrate the occasion by proposing to P-01s (an automaton who looks exactly like Horizon) he discovers that his suspicion about P-01s’ appearance actually has a basis in truth; P-01s is in fact Horizon Ariadust, reborn into a robotic body. In addition to this, Horizon’s emotions had been stripped away and are now stored in eight powerful weapons called the Mortal Sin Armaments; which are now in the possession of key people in various established countries in the Divine States.

To retrieve the emotions of Horizon Ariadust, Toori Aoi along with his friends and allies begins a crusade against different obstacles as key events in history are recreated in a futuristic manner.

A calculating merchant of noble birth lives a comfortable life managing his guild's business at the Imperial Academy—until lightning strikes him, leaving him with prophetic visions of a disastrous future. In these visions, he's expelled from his family, branded a traitor who aids demons, and worst of all, becomes a penniless beggar. When the supposed “protagonist” of these prophecies enrolls at the academy, he realizes his countdown to ruin has begun. Now he must use his foresight to rewrite a story where he's cast as a third-rate villain, all while navigating ancient dungeons, demonic threats, and the troublesome “hero” who might be the key to changing his fate.#MoneyIsEverything

As a useless spoiled wild child, Bai YiHan finally brought about the end of his family, chased away the one he loved and caused his own death. After rebirth, he decides to cleanse himself and work hard at being a good child. But a lot of things don’t seem to be as he expected…

Bai Pa + Bai Ma: My son’s so obedient. Someone must be bullying him. This cannot be forgiven!

Bai Big Bro + Bai Big Sis: If my little brother’s sensibility comes from his suffering, then I’d rather he be a spoiled brat forever!

Mu JingYuan: If HanHan hits you, you must accept it. Yet you dodged…The wind’s changing. Someone should be bankrupt to make HanHan smile.

Bai YiHan: …I was so wild in my past life. Your involvement are undeniable!

This story is speculative, speculative, speculative. Important matters must be said thrice. Everything is about speculative time-traveling.

- Description from Novelupdates

The only way to stop the earth’s doom.Is to seduce the girl who is the student council president.