Inma o Fuuin Suru Dake no Kantan na Adventure

Succubi conquered the world, taking their pleasure from humans like locusts on a harvest.
Consumption was outpacing supply. At this rate, humankind would go extinct.
Some humans survived the fate of a seduced death and plotted their counterassault.
The key was a magic seal called the Succubus Ring, which absorbs souls.

The succubi wanted the Ring,
lust demons wanted the humans,
the world was awash in all kinds of desires--......

"Hahaha... I'll turn you into a succubus too.....
You will be my special pet!......"

[From DLsite English]