As a high school student, I loved Frank E. Peretti's This Present Darkness and its sequel Piercing the Darkness which gave us a look into the roles of angels and demons in their spiritual warfare that surrounds our daily lives. I have always wanted to write a similar sort of fiction, but found all of my attempts to be too derivative of Peretti's work.
While this statement might make some people decide that it's time take my measurements for a straitjacket, I have felt the presence of angels and demons in my life. Sometimes they are the inner voices (like the cartoon representations) that give me conflicting statements in regards to my actions; sometimes there is a more physical aspect, a reflex I didn't know I had, a movement caught out of the corner of my eye.
I believe that a guardian angel would be the perfect video game character to play. While the protected person goes about his or her normal life, we would take the role of the guardian that keeps the forces of darkness away. It would not need to be an earth-shattering plot, but just the daily dangers that our protectors keep from causing lasting harm.