Inma no Shiro ~Bakunyuu Succubus no Yuuwaki to Kyuusei~

At the end of his long journey, the hero arrived at the demon castle as foretold.
There, a phalanx of curvaceous succubi appeared, whispering their siren song.
"Forget your world. Be with us, take your reward."
The hero knew he mustn't be tempted, but those voices... those curves...

[From DLsite English]