The translation could use some proofreading work, particularly in the way the sentences are structured.
I wouldn't go as far as to use the "poor grammar" tag on this work (although are are a number of spelling and grammatical errors here and there), but most of the sentences are awkwardly phrased. Here are some cleaned-up examples from the first two pages alone:
P1 Box 1: Succubus: A temptress who enslaves men and bestows upon them the highest form of pleasure through sexual intercourse. Box 2: In return for such pleasure, she receives the semen and life force beloved of her race. Box 3: These ladies are such terrifying demons that people who perform sexual acts with them just once will continue to do so until their life forces run dry. Box 4: Because their existence is as dangerous as that of other monsters, Box 10: this hostile succubus, who were captured by a human, are forced to kneel down.
P2 Box 1: This is the man who subjugated the succubi. However, his twisted desires run in contrast to the immense sorcery that gives him the capability to perform such a feat. Obsessed with the hunt for women that he can freely rape, he has set his eyes on these inhumane succubi. Box 2: With their power completely sealed off, these ladies have become his own playthings. Box 4: and their ability to drain life through sexual deeds was also taken away. Box 5: There are no options remaining for these ladies whose bodies ignite the lust of men, so... Box 6: their fate to become his "meat slaves" is inevitable.
He knocked them up so it's not so back. At least he got to pass on his genes, which 70% of men throughout history never got to do so he's a winner in the eyes of evolution.