I heard about this from e;r. We all sorely needed this kind of content. Too much stuff with monstergirls is so permanently debauched and singleminded, it becomes boring. Even otherwise great games like Crimson Veil that let you play out the idea of a flawed hero who can succumb to her Lust and become the villain (while still being written sympathetically as the monster) become somewhat distracting when it flashes naked women at you and tells you "Hey, isn't this AROUSING!?" - although I suppose it's kind of the point to show that you aren't immune either. The idea of monsters less as demons and more as youkai or fey who aren't irredeemably defiant of God's will but are rather simply original sinners like us - and even outright worshipping Him is VERY interesting and new!
And to be honest, the idea of a Christian succubus reminds me of Planescape: Torment and its Brothel for the Slaking of Intellectual Lusts. After all, if one can be born a demon or a devil, can one not escape that life? The real demons were born angels but fell of their own free will after all.