The concept of meeting a Magic User from Equestria's distant past who had entered and settled down in the Human world centuries in the past and are still alive and active even after so many years. Their magic halting the aging process and granting them longevity. This being accomplished through a myriad of ways. Rituals, magic artifacts, the creation of a magical environment (usually a residence such as a House or Mansion) of which exposure to the magic permeating from it would grant them long life and eternal youth, etc. The possibilities are up to the writer.

Said magic user could be best described as being an elderly person in a young person's body. Although they stopped aging and still retain their youthfulness, they act and think like an older person minus the senility. Especially since they'd have experienced and live through a good length of Human history depending on far into the past their entry into human world occurred."

Like imagine when this magic user is introduced, they appear to be at the same teenage and young adult age group as the other characters and yet they act and think and in some cases talk like a much older person.