So, I've been thinking about this idea for a little while. A GPSL based around angels and demons mainly, but maybe a few humans thrown in there. Basically, the “spirits” of angels and demons continue cycling and maybe “taking turns” on earth and in heaven/hell. Granted we'd only be playing out the on earth bits and pieces. Forgive me for grammar/spelling errors. It's late and I wanted to get the idea down somewhere.
The way I'm thinking is that when they are born they don't have any recollection of their past lives or heaven/hell. They go through everything from infancy to adulthood. Of course there are hints at their past live for instance certain extreme feelings trigger small glimpses of powers (if they have any, not all will) or they have nightmares & dreams about their past lives. However, when they turn 25 exactly everything floods back to them, memories, full powers (again, if any) everything that has to do with their spirits. I'm thinking that they stop aging at that time until or if they decide that they themselves want to start a family. Once they have their first child their aging process resumes and they live out their lives until they die however that might be and they go to heaven or hell and again await their time to be born again.
I'm thinking that as “parents” they are either gifted a child based around how they lived their lives so even if an angel and an angel found each other, if they had made a drastically bad decision, I don't know say, murder, they could have a child with the spirit of a demon.
I really would just love to expand on this idea and brainstorm it out with a few people to see if we could come up with something great. As for what I've thought out so far. I've linked it down below on what I've thought about and what can be tweaked, again, SO FAR. Feel free to shoot me your ideas and let me know if you're even interested.