Shinwa Densetsu no Eiyuu no Isekaitan - Volume 10, Chapter 1 – Wriggling Darkness, Part 5

Endless sky and infinite space, the cosmos isn’t some paradise waiting to be found, it is full of darkness and danger, death and terror of the great unknown. However, for that glittering swath of blue, we have no fear! For the longevity of men, we have no regrets! Nothing shall stand in our way because it is finally our time, our age! The age of cosmos exploration!

The Queen of the elves wants to bear his child, the vatican’s saintess is his maid and the empire’s princess wants to elope with him.

But his only concern was his delusion of taking down the creator of the world!

- Description from Novelupdates

A 13-year-old deaf teenager living in the 21st century suddenly found himself as a young boy in Japan during the early 1900s. With two World Wars, two nuclear bombs, Hitler and many other disasters awaiting his future, he thought things couldn't get worse.Except it did.He found out later on that he had actually reincarnated into the world of Demon Slayer where man-eating demons ruled the night. He thought things couldn't get worse.Except it did.But hey! At least he had unparalleled talent, incredibly special eyes and future knowledge.How will the story of Demon Slayer change with the addition of this unique character? Will so many still die if the Hashiras had one more pillar in the final battle?Or will the story end on a much happier note?