I assume this was based on a visual novel(prob of the 18+ only variety)? It looks/sounds like it. Maybe I'll check it out next time I have Funi if they still own it.
This already looks better to me than that DQ5 movie. Although I've never seen/read the original version of this so if it completely changes the look it wouldn't ruin anything for me. (although from what I hear they also butchered the story of DQ5)