Death March kara Hajimaru Isekai Kyusoukyoku (WN) - Book 3 - 3-4. Little Girl and Night Turmoil

With a marriage contract forcefully done, he married her, and all she could do was comply, and resent him deeply for that and for all the following misunderstandings they faced.
However, it was already too late when she understood she actually loved him.

There lived an extremely miserable man- he suffered from a terminal illness. But one fine day, when he left his miserable body, a certain entity grants him another chance- another life along with few gifts to help him in his journey.The man is transmigrated into the body of a young man into an ancient society. Watch how the man lives his new life and conquers the world.[This book will contain R18 scenes but do not expect it to be the theme of the book. It will be mostly based on strategies and expansion of empire. A small advancement in the technology can also be expected.]

In the world of Aetheria, there is one name that is feared by all. Yet, he is known more for his title, the Demon General. Whether it’s Gods or Demons, no beings dare to oppose his authority. He ruled Aetheria with an iron hand. Cities are destroyed on his whim. Countries are razed at his displeasure.This is the tale of his rise to power.This is the tale of his rise to Godhood.This is the tale of the rise of the Demon General.