I've always been interested in what an extremely wealthy and well-respected family would do if their son ended up being insane. Particularly if that family were slightly scared of their son, if only because he claimed he could see spirits and because the family priest said that such things were evil.
I would see this roleplay taking place in the past - anywhere from 1500's to 1900's...mostly to allow the family the luxury of having a manor home in a time where appearances were everything.
The son - the youngest in a family with two older sons and one daughter - would have been raised to be accepted into society but upon his increasingly shocking visions - visions of people who had been murdered, or his claims of hearing voices, of seeing ghosts - he would be hidden away in the manor and never let out. Naturally, he would dislike this treatment, and would seek ways to sneak out to escape the oppressive atmosphere of his home.
I would love someone to play a doctor that the family hires in the hopes of curing their son, or else someone who finds him wandering and takes him under their wing (this person could be anyone from a bartender to an opium addict), or a member of another rich family who sees him wandering about the estate when he comes to visit. Really, the options for whoever you would like are endless. I'd like to play the young man.