Need to avoid making it too generic. Add unique traits to each immortal beyond basic archetypes. Perhaps one has the ability to manipulate time, another to communicate with plants, etc. Also, consider their vulnerabilities if any. Maybe their immortality comes with a drawback.
Next, the history and lore. Why are they immortal? Perhaps they were transformed for a purpose, like protecting something vital. Maybe they have a connection to nature or seasons since the city's name has "bloom." Seasons changing could be a theme—each of the five represents a season, or maybe elements related to it. tale of immortal five bloomstenoke
I should also consider the tone. Since it's a "tale," a literary and slightly magical tone would fit. Maybe use some poetic language. Also, end with a note on why this tale matters, connecting it to themes like eternal guardianship or the cost of immortality. Need to avoid making it too generic