Elysium: Rise of the Dark King Ver.0.12.2 by Seyser Koze - Adult Sex Game

This is Elysium, a story-focused H-RPG made using RPG Maker VX. There's much more of a focus on the story aspect than the game aspect, making it more of a "more-than-usually-interactive VN" than an RPG
You Play as knight who gets betrayed for doing the right thing, turns to dark powers for revenge.