John is a super mutant who used to be in the nightkin division of the Master's Army. Though that was many, many years ago, John still remembers much of it. Unfortunately, he also remembers a lot of stuff that never happened. John's mind has been adversely affected by prolonged usage of Stealth Boys. His brain chemistry has been permanently altered, resulting in schizophrenia. John now sees visions often.
Though he has not officially converted to Mormonism, he respects the beliefs and rules of Jeremiah. Unfortunately, some of the Mormons believe that John may be a prophet. John isn't sure what's going on, but it makes him very nervous.