My Little Sweet Wife - Chapter 42 - Heavy Rain I

A girl who calls herself a demon appeared before a timid student named Fumio Kijima. The girl claims to be a campaign girl from the demon world and she gives him the ability to “summon a room” from nothing but thin air.

At first he doesn’t abuse his power and uses it as a convenient ability in his every day life. But one day he is bullied by his classmates under a false pretext and is made to suffer. In the past he would have wallowed in misery and cried himself to sleep, but now he had a power to call upon.

“I will make them regret it!”

Using his powers to summon his “room”, he begins his era of confinement and brainwashing to achieve his goals.

Transmigration is the total rage of novels nowadays, and if the main character isn’t careful, they get swept up into the bandwagon, so this is a story from another continent. Magic? —— of course the main character won’t know how to use it, but what about knowing how to use electricity? Dou Qi? —— the main character still doesn’t know, but is inner power more strong? Beautiful women? —— of course the main character has them, or else there wouldn’t be anything worth reading in this novel. How many? —— that question’s quite good, if I told you everything, what would you read for? An honest warning to the female readers and your tastes, it is a harem novel, don’t read it if you’re not interested. A stern warning to male readers and your tastes, um, it’s like a breath of fresh air.

- Description from Novelupdates

Martial Arts Grandmaster，who achieved the limit of human body, can fight a hundred foes alone as the founder of styles and schools. Yet, they could only reign supreme in ancient times. But the Immortals... Flying on the wind without relying on, they travel through the Azure Void, heading to the Northern Sea by dawn and reaching Cangwu Realm by dusk. Feeding on the wind and drinking the dew, transcending the mundane world, wandering freely with eternal life. That is humanity’s ultimate romance. Are Immortals fictional? Do they not exist in the real world? The outcome depends on the individual! The Martial Path was originally a defiance of the heavens, surpassing limits, turning the impossible into possible! So, what is wrong with desiring to become a Human Immortal, journeying to the Northern Sea Star by morning and reaching the Cangwu Realm by dusk? This is the story of someone in the modern world of martial arts who, armed with just a bit of informational advantage, ultimately became a Human Immortal and shattered stars with a single punch.

Long Fei, a cross-timer and doujin, is an otaku who traveled to another world. In the original world, he was an otaku fan of Gundam and military science fiction.

He died in an accident and was reincarnated into another world. The Gundam works he had read before his death and the techniques in various military novels could be brought to another world.

How would he use the Gundam that Long Fei created? What waves can be caused in this different world?