Shuumatsu no Harem Fantasia - MangaDex

It's year 998, and the world has been corrupted by darkness. The next head of the small border kingdom of Nagara, Ark, has feelings for his cousin, Aurelia, but a political marriage to the Crown Prince has separated them. In order to get her back, Ark desires immense power, but a mysterious dark elf, Rati, appears in front of him. In exchange for a promise, she will give him "the power to rule the world." An erotic and dark fantasy begins!

Chapters and Volumes/Fantasia, World's End Harem Wiki

Chapter 39 (Brazilian Portuguese) - Shuumatsu no Harem Fantasia Gakuen

Read World's End Harem - Fantasia Vol.6 Chapter 23.2 - Manganelo

Shuumatsu no Harem Fantasia Capítulo 21.1 – Mangás Chan

World's End Harem - Fantasia

DISC] World's End Harem Fantasia Ch. 18.1-18.2 : r/manga

DISC] Shuumatsu no Harem Fantasia - Chap 20.1 and 39 -Question in the comments : r/manga

World's End Harem - Wikidata

Isekai Kimagure Burari Tabi ~Dorei Harem wo Soete~ - MangaDex

1 Chapter 58 - Shuumatsu no Harem Fantasia - MangaDex