http://www.dlsite.com/maniax/work/=/product_id/RJ179039

Story
In a multi-creatured world, a succubus queen rises
using her power of lust to sexualize the other species.
The human species faces extinction at this rate,
so one man takes a stand to stop the succubus......

Genre: Battle F*ck RPG
Fetishes: Standard ~ Masochist Male
CGs: 33 patterns + variations, etc.
Difficulty: 3 options

Situations
Breast sex, girl on top, creampie, handjob, footjob, cunnilingus, piss drinking,
masturbation on command, size fetish (tiny man), energy drain, tons of cum, more.
Lost battles are rewarded with r*pe by monster girls.