World’s End Harem: Fantasia Vol. 1

In the year 998 of the holy calendar, the world is undermined by darkness and will soon come to an end. Arc de Rezare Nargala is next in line to rule the small country of Nargala and is in love with his childhood friend Aurelia. However, the two are separated when she is forced into a political marriage with the crown prince. Arc longs for the power to win her back and is approached by a mysterious dark elf named Lati. In exchange for a promise, Lati assures him the power to rule over the world. The curtain rises on an erotic dark fantasy!
Notice: This book is written in Japanese.