This show has plenty to hook the viewer straight away. You can't help but want to cheer for the young Duke and his love. His curse is truly horrifying and the loneliness he is forced to endure at his age makes me want to watch him find happiness in the end.
But that interest can only sustain me for so long. I realized very early on that this seems to be based off of a gag manga where the running gag is that the busty maid teases the young Duke by playing on his sexual attraction and budding love towards her. Had I enjoyed this gimmick, perhaps I could have kept watching. But I felt that this got tiring real fast. I may have accepted it had this been only 12 episodes long, but when I checked the manga and saw that there are over 190 chapters, I was overwhelmed. I don't think I can sit through multiple seasons of this same tired gag. When the Duke failed to make much headway in solving his case the first time he met the witches', I had to stop watching.
I was only watching to see the love story succeed. An entire saga about the two of them stuck at the same stage of their relationship seems like empty filler content to me. This si the same reason I stopped reading Nisekoi in the middle. Maybe if there had been some interesting variations to the gag, the way Kaguya-sama does it, I could have kept watching.
It's a shame because the music and animation are pretty good. The CG especially is much better than I'd have expected.
