I'm trying to remember the name of an anime that I only vaguely remember seeing. It's kinda old though so I don't know how much you guys can help. Let me make a list of things I vaguely remember

>set in a demon world/city very modern
>very poppy art style lot of solid blacks
>main character was a doctor or something, may have been wearing a hawaiian shirt
>there are a bunch of cool lookining demons
>pretty boobalicious demon girls too
>think the main character may have been a skeleton or vampire or some thing
>ends in a sort of cliff hanger

Hopefully I can get some help.