The Greatest Mecha - Chapter 25: What She Didn’t Say

An ordinary youth living in the year 2050 in the Western calendar accidentally came to a fantasy world created by the collision of magical elements and supernatural technology at the other end of the dimension…

- Description from novelbuddy

Shu Yu transmigrated to become a mob character, exiled into oblivion after appearing twice after helping the female side character who kept trying to dig a deeper hole for herself.Realizing she couldn't change the outcome, Shu Yu decided to just goof off.But even before the exile came, she was suddenly told that she was not a daughter of the Shu family.She was born to a farmer's family, who were so poor they couldn't afford to repair their leaking house. Having decided to eliminate the tarnishing of their good name, Shu Yu's adopted family decided to murder her.Shu Yu: Come on, see who dies.Returning to her biological family, the sight of a plate of salted vegetables, a barely-full bowl of rice, and her real parents' nervous looks, she finally sighed.No more goofing off, or she's going to starve to death.

Kawaki, who was born in the dragon vein of a planet (Altana), first met Umibozu who was traveling in the universe, and his girlfriend, Kouka.Later, he came to Earth by accident and met the teacher who affected his life —Yoshida Shouyou.He also met a group of friends. The most conspicuous among the group of friends is a fool with silver hair and naturally curly hair, a short man with purple hair, and a little devil whose catchphrase is “Not Zura, it's Katsura!”Gintama Doujin, not transmigration.

The aliens came with hostility.
Facing the invasion of aliens, human beings are weak like ants.
So this is the end, the real end.
But there is resistance when there is an invasion.
For some, this is not the end, it is war.
So this is war.
Real war!

- Description from Qidian