A supportive board for writers at all levels to discuss writing topics, debate burning issues related to publishing, To publicise your novel. And to seek support of every kind in helping you to become a better writer.
Make it an earthbound guardian angel, like Blade Runner and The Prophecy. A horror story, like del Toro would write. A codependent guardian angel with anger issues. Always makes it about himself
Like the guardian angel was there to throw you out of harms way.....fun fun fun...I would love to see/ read how you swing this....you caught my interest....
Wrote a romance a lifetime ago where she thought he was an angel but he was really a Chicago cop. Not sure I could get away with the deception part of it though 
Well if I didn't need my guardian angel right now, you could borrow mine. The stories mine could tell you, but I'm not through being dumb yet!..... great story idea though.