diabel is not even a demented character, i dont understand how u came to that conclusion. he shares the same goal as ayana and even sacrificed his soul to become a devil FOR her to have a future with ppl she holds dear. he doesnt prevent her from building relationships with other ppl. he doesnt care for anyone but he doesnt mindlessly kill other ppl like what erez has done again and again. his love and possessiveness is not destructive to anyone but himself.
understanding character motives and behavior ensure u understand the story

When two main ml are so twisted and insane that I kinda lwk agree mc to be with rox atp bro's too chill and healthy compared to those twos